If you're in East London anytime before August 4, 2013, you can climb these walls without fear of falling. It's an optical illusion created by Argentinian artist Leandro Erlich called Dalston House. Here's how it's done.
The "house" is on the ground, with a giant mirror looming over it at an angle. The work was commissioned by the Barbican in London.
See more pictures at Colossal. Link -via Geeks Are Sexy
Previously: More of Erlich's illusion art.