I did this once! I don't remember all the details since my older brother planned the excursion, but it was quick to get out of the airport on the tube. We went to Trafalgar square and then walked about by Westminster Abbey, Buckingham Palace. ect. We also had time for lunch and one other tube trip to a shopping area my brother wanted to visit.

I would just create a list of the top things you want to see and set the time when you need to head back to the airport.

I just wanted to note: make sure you give yourself plenty of time to get to your flight at Heathrow. My husband and I just got back from Dublin going through Heathrow as well and it took us nearly two hours just to get to our connecting flight (security, airline lines, etc.) Have a great time!

Well, first it's not really an 8-hour layover. Because you're leaving the airport, you need to check back in and go through security again. Chances are, it's more of a 6-hour or 6 and a half hour layover. With that in mind, factor what is near the airport and within walking distance. The less time you have to spend on transportation, the more you can maximize your time to actually see the sights. I'd avoid anything extremely touristy because you'll spend more time standing in a line or going through crowds.

Get on the tube (subway) and go into the center, (Regent street? you'll have to change at Baker Street I believe, easy to do) and you should allow about 2 hours each way for the trip (it really shouldn't take that long but I guarantee if you don't leave yourself plenty of time, especially for the return leg, you will have unexpected delays. That's just how it is.). Four hours in the center of London is plenty of time, especially if you head down Regent Street (past Liberty of London) to the Trafalgar square area-loads of the big national art galleries, China town and Covent Garden a few minutes walk away. Don't even consider heading east (Hackney direction) as you'll run out of time, you want to stay central or west, because that's the direction of Heathrow.

Good luck and have a great time!

the tube to the center of town takes 45 minutes..
the heathrow express takes 20 minutes.. trains a little bit more.. taxies are really expensive...
just remember that you have 8 hours: 1 for the trip to and from the center, 2 hours for checkin and security clearance...

I've been in this situation in London and I have to say that it might not be enough time to get and about.

Find out if you're immigrating as you exit Dublin. Many trips out of Dublin have you in transit and you won't be allowed to leave the airport in the UK at all.

If you are allowed to leave the airport, consider the time it takes to get out of Heathrow. Heathrow is a city unto itself, and you don't necessarily pop out of the terminal, onto a train, and end up at a great destination. I've spent up to two hours getting out of there, and it's a nightmare.

If all of those things do work in your favour, consider traffic, queues to get into attractions, and the trip back to the airport (can be harrowing during rush hour), you might just consider getting a decent book and hunkering down. You'll probably have just enough time for a meal and a couple of pints at the airport pub.

Hey there - being as we are originally from London, sofa.com's New York team would like to throw in our tuppence worth!

The quickest way to get from Heathrow to London is the Heathrow Express to Paddington station, which is well connected with the rest of the underground. The Heathrow express costs about $30 per person, and takes about 15 minutes. From Paddington, take the Bakerloo line on the underground to Piccadilly Circus for the "WOW I'M IN LONDON" experience plus chic shopping on Piccadilly (afternoon tea at Fortnum & Mason, Burlington Arcade, Bond Street Boutiques, a glass of fizz at the Ritz hotel bar, etc). Or head North up Regent Street for trendy high-street shopping all the way up to Oxford Circus & Oxford Street.

If you go 3 stops further on the Bakerloo line from Paddington [total 15 mins], to Waterloo Station, you can wander along Southbank to see the Tate Modern, The London Eye and all the fun street performances, restaurants and amazing river views along the Southern Bank of the Thames. If you have time, seriously think about grabbing a cocktail and a bite to eat at the top of the OXO tower and take in an even cooler view of the city.

Top tip: do a couple of things thoroughly - don't try and see the whole city in one day or you'll stress yourself out and you won't have a good time!

Have fun,

With love from the sofa.com team in Chelsea, New York City!

x

I did this on an organized trip. I think we took a bus to Windsor Castle and just kind of walked around.

I would pick a place closest to the airport and just do that one thing. Dont go overboard

We were there on a Sunday and everything was closed! haha

London is an amazing city! I know it's the "touristy" thing to do but the double decker bus tour is a really great ride and you get to see most of the known spots. Regent Street is great (as the post above states) as is Notting Hill... especially if it's a market day!

I would take the Heathrow express train return to the centre of London. This way you are only really spending 30 mins on transport and you can enjoy some sights in the city before getting back to the airport!
https://www.heathrowexpress.com/?gclid=CJCwt6D1oLECFYio4Aodd0_BZA

I second (third?) the suggestion of the Heathrow express. It was amazingly quick. I'd also confirm the warning that you should allow 2 hrs to get through all the tunnels and queues back at Heathrow. But even 4 hours downtown will be fun and better than sitting at the airport. See if you can stow your carry-on somewhere, too.

Jump on the Picadilly Underground line at Heathrow; it is about 40 minutes into central London. If you want to see London's "greatest hits", so to speak, get off at Westminster and see Parliament, Big Ben, the London Eye, Westminster Abbey and the Thames all in the span of a few minutes. Trafalgar Square and Buckingham Palace are short walks from there. I'd make a mad dash to the British Museum and/or British Library if possible; both are incredible. Just make sure you allow yourself plenty of time to get back to Heathrow; the Tube is packed at all waking hours. Have a great trip!

Definitely splurge and take the Heathrow Express trains back and forth. It sounds like you really should factor in about 3 hours for travel time to and fro and getting back through security. I've only been through security at Heathrow for 8:00am flight (to Dublin, ironically) and it was a nightmare! All the business folks flying over for meetings, etc.

With roughly four hours in the city, I would go to the London Eye. By the fall, you shouldn't have too much of a wait. Plus it's by Big Ben and Westminister, so you're knocking out several icons all at once. Take the Circle Line from Paddington to Westminster. If time allows, buy tickets to the hop on/hop off double decker tour bus. It will give you a good overview of the city. I usually ignore such touristy things but in this case, you will get to see all the sites. I don't think it's worth all the tube hopping to do it on your own. But if you're adventurous, most of the good sites (Buckingham Palace, Covent Garden, etc.) on the Piccadilly Line. Good luck and have fun!

As a frequent traveller and London resident, all I can say is good luck. This isn't a great idea with a city like London, especially if your eight hours does not already include a 2-3 hour check-in window. You'll be stressed, exhausted and harried, which is how most Londoners feel most of the time, and not the best way to experience a truly great city. However, if you are determined, here's how to do it.

Your starting point should be Transport for London, who will give you a reasonably accurate estimate (without accounting for delays, which are frequent) of how long it will take you to get from point A to point B. My guess would be that the fastest way between Heathrow and the actual centre of town is the Piccadilly line, which will take you anywhere from Hyde Park to Kings Cross. This will take around an hour (and don't forget the hour back either!).

http://www.tfl.gov.uk/

What to do while you're here is a question that should actually be dictated by your interests. What makes London one of the world's greatest cities is not the Tower of London or Buckingham Palace, although those are always options, but rather the atmosphere, the music, the theatre, the people, the food. 7 hours is never going to give you a chance to even dip your toes in.

My recommendation? Pick one thing and do it right. Love Shakespeare? Walk down by the South Bank of the Thames (a favourite atmospheric spot for both locals and tourists alike) to the Globe Theatre, which is a replica of the original Shakespearean theatre built on the exact spot, which has an incredible view of St Pauls and the city, and do a tour or even take in a show. One of the few touristy experiences which is also incredibly authentic and carrying with it equal parts historic and cultural value. The restaurant there (the Swan at the Globe) serves excellent quality British food (made from local organic ingredients, showcasing one of London's newer trends, amazing food) as well as afternoon tea (another classic). It's also next door to the UK's finest contemporary art museum, the Tate Modern, built in an iconic old Turbine hall and chimney.

However, and this wouldn't be my choice, if you really want bang for your buck, visit the National Gallery on Trafalger Square - well connected (and on the Piccadilly line straight from Heathrow), which hits two iconic landmark birds with one stone. If you have time, walk down to the River down Whitehall past the Horse Guards parade and 10 Downing Street (where the Prime Minister lives), where you will hit Westminster Palace (with Big Ben and the House of Commons) and Westminster Cathedral. You can then hop back on the district line to Hammersmith where you can rejoin the Piccadilly Line back to Heathrow. No time for food on this one, but if you're starving, find somewhere that serves the greasiest fish and chips you can. Quick and dirty and quintessentially British.

The heathrow airport was extremely overwhelming! I just want you to know that!

The Heathrow Express may be quicker but only by about 20 mins and it's loads more expensive than taking the tube. Also once you get to Paddington you'll have to get on to the tube which takes ages as it's a bit of a rat run. You're totally best off hopping on the Picadilly Line (dark blue line) and going straight into the city to Piccadilly Circus. From there you can walk to Trafalgar Square, Big Ben, Embankment the whole lot.

As an Art Historian, I feel it is my duty to point out that all of the "big" museums (Tate Britain, Tate Modern, British Museum, Victoria & Albert) are conveniently located near the central sites mentioned above and have free admittance to the permanent collections, courtesy of Her Majesty the Queen :)

First, there's a "Left Luggage" place at Heathrow that will let you leave your bags there for a matter of hours -- not terribly cheap, but for me, worth spending the money so I can leave most of my carry-on there instead of schlepping it on me all day long.

Second, definitely the Heathrow Express! You'll be able to check times online before you leave home, so you'll know how much to rush to catch the train in the first place, and once you're on it, you'll then have a good idea of which one you'll need to get back to LHR in time to collect your carry-on, and go back through security.

Yes to Picadilly Circus! But beyond that, it depends on what YOU would like to see in London. Art? Tate Modern! Food? Fortnum and Mason. Trend shopping? Regent Street and Oxford Street (all conveniently near Picadilly Circus!) Posh shopping? Harrod's. Or sights? Big Ben, the houses of Parliament, and the London Eye are all really near each other, and pretty near Trafalgar Square. St Peter's isn't near anything, espeically if you're on tight timelines. I love the Tower, but it takes about 3 hours to see, and I think you'll probably want to see more than that.

For my money, if I had 3-4 hours in London to show a newcomer, I'd probably do Big Ben/Parliament/Trafalgar Square, take a cab through the Mall by Buckingham Palace, and then if it's a weekend, drive down to Borough Market for lunch. Best of Fresh Everything!

Sounds like a fab trip. Have fun!

Definitely spring for the Heathrow Express, and then after than, use cabs, not the tube. Mention to your cab driver that you're in town for just a few hours, and would love to be shown the highlights. My mother and I had great results with this technique ourselves once.

Hi! Had to chime in since we just did this in May on our way back from South Africa. We had 7 hours and we still managed to get in to town and back (and check in to a different terminal) for our flight home. I think the most important thing is to check when you are flying in. We flew in early on a weekday morning, so we got through security fairly quickly (our bags also went through to our final destination). We also made sure to head to our departing terminal to check our carry ons (we used the Left Baggage service for 8 pounds - totally worth it!).

I would recommend either the Heathrow Express or the Heathrow Connect. They both leave from the same platform, and the Heathrow Express takes 15 minutes vs 25 on the Connect. The Connect cost us 32 pounds return for two people; worth it in my opinion. The Express is about $25 more for ten minutes saved...

My final tip is to pick one thing to do/one area to visit and stick to it. We took the Connect into Paddington and then walked to Oxford Circus to do some shopping. You can also transfer to the Tube and head to Trafalgar Square and Soho for a great meal. We had a ton of time to wander Oxford Street to shop, check out the decorations for the Queen's Jubilee and stop for lunch before heading back to Paddington. I would definitely recommend it, but keep in mind that staying at the airport would definitely be the cheaper option.

i also sound a note of caution in terms of travel times... the heathrow express is of course faster, but it runs every 15 minutes (as opposed to every 2/4/8 for the tube). it also goes to paddington, so you'll probably want to tube/bus/taxi/walk it from there to see some sights anyway... can i suggest an alternative? don't go all the way into town. you can take the piccadilly line out of heathrow straight to south kensington where you'll find the victoria & albert museum (as mentioned in the 'design lover's guide to london'), natural history museum and science museum all in one place. there's also plenty of shopping to be done and harrods is within easy walking distance as well as multivarious eateries. take a stroll in hyde park if you really want to stretch your legs a bit. seriously, west is best... but them i'm biased ;0) enjoy!

The tube can sometimes take forever (an hour or more if there are delays, and there are always delays and line closures on weekends). The Heathrow Express is probably your best bet for time efficiency. The tube is easy to navigate once you're in town, and I'd recommend the Westminster station for that "Wow, I'm in London" feeling, since you exit the station directly across from the Parliament buildings and Big Ben. Nearby is the London Eye, Westminster Abbey, and Buckingham palace - all easy walking distance.

If you want to hit most of the big sights without actually going inside, a hop on/hop off bus tour is a great option, and you'll get a nice little tour of the city (including The City, which is where the Tower of London is, and St Paul's). You'd be hard-pressed to see much otherwise.

Make sure you can check your bags into storage at the airport. You don't want to wander the town with them. And give yourself plenty of time to get back to go through security again. Better safe than sorry. Heathrow can be very busy and lineups move slowly at times.

I live in London and must echo the others that suggest the heathrow express. If you take the piccadilly line in it will take much longer than 45 mins and thats not counting delays. The safest and easiest thing to do probably is take the heathrow express into paddington, then take the bakerloo line to baker street. From there you can take one of those hop on hop off open top bus tours which is the easiest way to see the the most popular sites. Your ticket for these buses are valid for 24 hours, so its cheaper than taking black cabs and getting stuck in traffic.You can then gauge your time and decide what you actually want to hop off to see, but keep in mind although things are close together, it can take ages to get from point a to b with traffic, especially now with the infamous olympic lanes open.

If you want to hit the big sites, others have good suggestions. But if you want to go one fascinating place, I have to put in a plug for my favorite museum that I've ever been to anywhere, the London Transportation Museum. It's basically a history of the city as seen through the changes in modes of transportation. If you're at all into urban planning, it's kind of paradise.
It's at Covent Garden, http://www.ltmuseum.co.uk/

I will add to the chorus of those telling you to be careful about time, though. Heathrow's a tough airport, and it's not a short trip into town. It sounds like a dreadfully long time to sit at the airport, but the truth is that you'll be pressed for time if you venture into the city, whatever you choose to do.

Second the suggestion for Windsor castle. It's a more manageable destination, very British, and there's a direct public transport bus from Heathrow.

(I did this on my way to South Africa and I was allowed out of the airport on my US passport- not sure why going to Ireland you wouldn't be allowed out)

@ICEXPAT: It would depend on the airline. Some airlines flying from Dublin to the US have you immigrate in Ireland, so your status is "in transit", even if you have a lay-over. This very thing happened to my sister-in-law this week.

This also happened to me 5 years ago when I had flown from Edinburgh to Boston. I had a 12 hour lay-over and wasn't allowed to exit the airport because we had "immigrated" in London to the US for the second leg of our trip.

If you've only got 6-8 hrs the Heathrow Express is a must and I'd leave plenty of time either side. Security there can take forever to get through sometimes!! However, if you just want to go for it and see as many sights as possible in around 6 hrs and perhaps pick up some places to visit properly next time how about the following? (Which will also stretch your legs and tire you out for the journey home! I'm so considerate!!) (Below the description is a link to a map if you get lost in all the text!)

Heathrow Express to Paddington then the Circle or District line (yellow or green) round to St. James' Park. Walk across the park and you're out at Buckingham Palace. Then walk down The Mall (where the crowds gathered on the Jubilee), through Admiralty Arch and you're in Trafalgar Sq where there's usually something going on. Turn right from Admiralty Arch and walk down Whitehall, past the Cenotaph war memorial and Downing St (where the prime minister lives!) onto Parliament Square. You can see Westminster Abbey (Royal Wedding) and then turn round and look at the Houses of Parliament and Big Ben before walking over Westminster Bridge. Over the river you can walk down the steps and if you've time go on the London Eye (big wheel and you can pre-book a time in advance or if it's a quiet day it's a 25min journey up and over plus the queue) then next to the wheel is the pier. Jump on a Thames clipper here and see sights like the National Theatre (aka concrete monstrosity), The Globe, Millennium Bridge, HMS Belfast, the Shard, Tower Bridge and get off at Tower of London. You'll only have time to jump on the next boat back North unfortunately but you'll see the Tower! Returns are about £10, you can sit in or stand outside on the boat and there's a bar! If you've got time at the south bank when you get back carry on walking down to the National Theatre where there are outside exhibitions and stuff going on most of the time. Then follow signs for Waterloo station just behind South Bank and jump on the Bakerloo line for Paddington and back to the airport.

The walk is about 2 1/2 miles (about 2+ hrs if you're stopping to look/take pics? I walked from the National to Trafalgar Sq last night with a friend in just over an hour) and leave a good 1 1/2 hrs for the boat. Another 45-1hr for the London eye. There's a site called walkit.com that you can plan walking routes on so you could customise a route and it will tell you how long they take to walk at different speeds. I've put the route I've described here on as an example, plus the orange 1 and 2, which tell you where you can get the clipper and where to change:

http://walkit.com/themed-walk/london/local-interest/linniestorm/walking-tour-of-london/

I GUARANTEE you be absolutely knackered by the time you get back to Heathrow and will sleep all the way home.

I did this once. With a 7 hours layover. I took the express to the London Eye, sprang for the express line there (super expensive) and had enough time to leisurely stroll to Buckingham Palace and then to head back. I had more than enough time at the airport to kill and wished I had added an additional attraction.

The London Eye (if the weather is nice) does give you a great view of the city. Not sure I would have picked it if the weather had been quintessentially lousy.

This is perfect. I have a 10 hour layover from 10 am to 8 pm on a Saturday in August. I don't care about the sites though. More interested in getting the flavor of london, as in lots going on, great bars/ restaurants/ shopping. Any suggestions for me?

My vote is for tube on Piccadilly line and transfer to the Circle line to get to Westminister. While it will take about 40 minutes, I believe when most people think about seeing London one cannot help but think about walking past Parliament.

When I was showing my sister around London, we had one mad dash day where we started near the Tower of London, crossed Tower Bridge, walked along the South Bank of the river all the way to Parliament, went by Buckingham Palace, then through Hyde Park where we had tea at the Orangery in Kensington Palace (also where they have the Princess Diana museum and where Will and Kate live when they are in London). There is nothing quite like telling friends at home that you had afternoon tea at a palace. If you are up for a good deal of walking, I would suggest walking as much of the river as you can. I think it is a better use of a short time to see many sites from the outside than deal with the giant lines to see the interior of one place.

I have taken the express from Paddington. It is a mess of a station, like trying to navigate Grand Central Station. It takes a bit longer, but the Tube is easier to navigate and has a lot more options of stops. Plus I don't think you can have a true experience of London until you have heard the Tube voice say, "Mind the Gap." And for the truly juvenile part of me... "this train is for cockfosters." Which you will hear on the Piccadilly Line going North.

Keep in mind that with the Olympics on you should really double check what's happening on the day you're in London. You don't want to get caught in mad transportation rush or mad airport rush...

As many have said - don't try and overdo it. Double decker bus is a good call if you want all the 'sights'. Alternative, and the favourite thing I do with visitors when they are in town, head down to Tate Modern, jump on the boat to Greenwich. Without you having to get tired walking, you get to float down the river past London Eye, Houses of Parliment, Shakespeare's Globe Theatre and end up in Greenwich, home of the cutty sark, the original maritime observatory, greenwich mean time, gorgeous little market, cute pubs, houses and classic London vibe. Gives you tourist sites and a feeling that you are seeing a slice of proper London, all wrapped up as an easy few hours!

Plan no more than 3 hours sightseeing and you should do it (first check there are no transport problems online in Dublin). I disagree strongly with the person who said stay close to the airport (nothing to see). Heathrow Express train runs to Paddington every 15 minutes and takes 15 minutes. Black cab from there to Westminster Abbey (if you go in that'll be your major sightsee could be queues - don't miss the waxworks in the cloisters, no queues - ask; if not pop in St Margaret's also interesting). "Clock" Big Ben and houses of parliament, along Whitehall to Downing Street and Horse Guards Parade (see Trafalgar Square & Nelson's Column in the distance). Through Horse Guards Parade to St James's Park, stroll through park to Buckingham Palace then right through Green Park to Piccadilly. Food Hall of Fortnum & Mason's and (if there's time) a cup of tea. Cab back to Paddington and back to Heathrow. Check it all out on Google Maps and streetview first.

For those in London longer, check out the (much cheaper than the tour bus) No 11 red bus http://www.tfl.gov.uk/tfl/gettingaround/maps/buses/ Probably not worth it for one day though as you'll have to buy and load an Oyster card. The boat from Westminster Pier to the Tower of London would be a good alternative view of the city but check you've got enough time.

I'd like to throw in my 2 cents to make sure you're at the airport the full 2 hours ahead of time. We were in Madrid coming back the the states and got there 1 and a half hours early because we were running late and they wouldn't let us check our bags which meant that all our whiskey and olive oils from our European vacation got thrown away because they wouldn't let us carry them on.

I have been scarred for life by this experience and have made it my mission to warn/remind everyone that those airplane rules are no joke.

It doesn't sound like you really have 8 hours. Time for the trains, security again... I dearly love London but I'd be hard pressed to recommend trying it. If you do, either pick one thing you really want to do or just do something like a quick wander down the Thames from Big Ben towards St. Paul's and call it a wrap when your clock runs out.

My last visit to London was in September a few years ago, though, and that time of the years was wonderful. Beautiful weather in the afternoons and the shoulder season so really no massive crowds to speak.

I live in London! DON'T get the tube as it is really slow into central London - instead, get on the Heathrow Express which takes 15 minutes. It costs a little more (about £15) but is worth it to get the most out of your one day in London.
To know what to recommend it'd be helpful to know what you're into - if you'll be there on a Saturday and are as into thrifting as most AT readers I'd recommend heading to Notting Hill and checking out the Portobello Road street market which is huge, in a pretty area of London surrounded by nice cafes and pubs and also very near the station (Paddington) to take you back to the airport.
Another thing you could do, also on that side of town, would be to head to Kensington and see the Natural History and Science museums - good on a rainy day!
Don't try and see too much - London is big, very crowded and quite slow to travel around. I would pick one thing/area and just see it properly.

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