I like to imagine that the expression "when in Rome" was coined by someone very eager to partake of the Roman lifestyle: great food, rich culture and beautiful, historic architecture wherever you look. Its very long history, two and a half thousand years, leads to Rome's name, "The Eternal City," or, perhaps it's because once you visit, you never want to leave.

See:

• The Sistine Chapel: It's perhaps the most famous work of art in the world, so don't miss it. The Vatican museums are smartly designed so you can slowly wander for hours or speed straight through to reach the chapel. While you're there, stop by and say hi to the Pope.

• Villa Borghese: This former estate, just north of the center of Rome, began as a vineyard but is now publicly owned. The grounds include lovely gardens with grassy knolls, shady paths, a small lake and even a zoo. You can stroll, feed the turtles or rent a bike.

• Ponte Sant'Angelo: A beautiful, ancient bridge across the Tiber. It's decorated with ten angel statues sculpted by Bernini, his last work before his death. Now the bridge is for pedestrians only, and walking across it provides some great views of Rome.

• La Bocca della Verita (the mouth of truth): This is worth a visit just so you can pretend to be Audrey Hepburn in Roman Holiday. It's located in the Church of Santa Maria in Cosmedin. Legend has it that if you put your hand in the mouth and tell a lie, it'll bite off your hand. I've never been brave enough to fib and see for myself.

• The Pantheon: It's a structural triumph and a design lover's dream. The world's largest unsupported dome is made possible by coffers (molded concrete), which lighten the weight while still providing strength. They're functional but also amazingly beautiful, especially with the beam of light coming through the open oculus in the ceiling.

Tour:

• Galleria Borghese: This museum is located in the 17th century Villa Borghese and houses works by many Italian artists, but the real stars are the Bernini sculptures on the lower level. You must reserve tickets ahead and visits are limited to two hours, but you can always stroll the gardens (see above) before or after you get your fill of art.

• Keats-Shelley Memorial House: If you love the romantic poets and the macabre, check this out. The memorial house and working library is at the base of the Spanish Steps and houses mementos like a lock of Keats' hair and an urn filled with Shelley's cremated bones. Both men died in Italy, Keats of tuberculosis in 1821, while Shelley drowned a year later with a copy of Keats' poems in his pocket.

• Pasta Museum: Can't get enough pasta? The Romans know how you feel. This museum covers everything you'd ever want to know, from types of flour to cooking techniques to pasta machinery through the years. There's a ton of information, perhaps too much for the average pasta enthusiast, but you'll definitely be ready for lunch.

• The Colosseum: It may seem like another tourist trap, but do brave the crowds. The ancient amphitheater is both structurally and historically fascinating, especially now that the floor of the arena has disintegrated, exposing the labyrinth of tunnels that once held animals and gladiators before their fights.

Shop:

• Porta Portese: A huge and popular flea market, selling everything from antiques to clothing to oddities of all kinds. It's open only on Sunday mornings until 2 pm. Get there early (read: dawn) to get first dibs and avoid the crowds.

• Via Condotti: This shopping street begins at the base of the Spanish Steps and is lined with upscale shops like Valentino, Bulgari, Armani, Gucci and Prada, to name a few. It can be crowded with tourists, but it's worth a stroll if only for some very glam window shopping.

• Campo de' Fiori: This daily market, in the square of the same name, has been in business since 1869. It's packed with stalls selling fruits and veggies, meats and fish, and mountains of dried fruits, nuts and grains. They also sell flowers, although the name is thought to derive from Campus Florae (Flora's Square), named after Flora, the lover of the famous general Pompey.

Eat:

• Pizzeria Baffetto: The best pizza in Rome (Yep, I said it). Near the Piazza Navona, look for the line out the door of this small pizzeria. Fun fact: Baffetto means "chief capitan" and has become the nickname for the adorable owner of this joint.

• Il Gelato di San Crispino: No gelato is bad gelato but this is spectacular. There are multiple locations but my favorite is near the Trevi Fountain. Nothing feels more Roman than throwing a coin in the fountain (to ensure your return to Rome) and enjoying some stracciatella.

• Il Sapori del Lord Byron: If you're celebrating, this sexy restaurant is located inside the Hotel Lord Byron and recalls all the romance of its namesake. It's definitely upscale and reserved, but the menu is creative, seasonal and perfectly Italian.

• Sant' Eustachio: This café has been serving espresso since 1938, and they sure know how to do it right: it's thick and creamy, almost sweet. The building itself is still in full 30's glamour; you can't miss the gorgeous floor mosaics.

• Trattoria Da Gino: In central Rome, near the Piazza de Parlamento, is this small, hidden trattoria. They're known for classic Roman dishes, including the best handmade pasta you're likely to taste. Make sure to reserve a table because it's always crowded with locals and tourists alike.

Stay:

• St. Regis Grand: This historic hotel was built by César Ritz in 1894 and has been housing royalty and the well-to-do ever since (they even have a diplomatic entrance). It's a splurge, but it's truly luxurious and worth a visit, even if it's just to the very stylish bar for a Compari.

• Ripa Hotel: Located in the trendy Trastevere district, most sights you want to see are a short walk or bus ride away. The rooms are spacious and many have lovely balconies, great for people watching. The style is modern and colorful, almost quirky.

• Inn at the Spanish Steps: This building was the former home of Hans Christian Andersen and is now a charming and upscale inn. The rooms are furnished in classic Roman décor so you feel like Sophia Loren.

• The First Hotel: Just across the river from Vatican City, this serene, modern hotel is as central as you can get, and the rooftop restaurant has views to die for.

(Images: 1.Flickr user Heatheronhertravels licensed for use under Creative Commons. 2.Flickr user xiquinho licensed for use under Creative Commons. 3. Shutterstock 4.Shutterstock 5.Shutterstock 6.Inn at the Spanish Steps)