Benjamin Verdonck is literally nesting. The Dutch artist built a giant human-sized nest on the side of the Weena skyscraper in Rotterdam. Nest Rotterdam hangs 50 meters above the street and was accomplished in six weeks. Check out the materials list after the jump...

According to the Nest Rotterdam website, artist Benjamin Verdonck used these materials:

The crowns of twenty-three silver birches.
one birch
one willow
two straw bales
one bucket of spit
three bags of sand
twelve buckets of glue
nineteen cans of polyurethane foam

Via: Core77.