La Pedrera Barcelona
Officially known as Casa Mila, after the patrons who funded the project, but more commonly known as "La Pedrera", this is unquestionably the most unusual apartment complex you will ever encounter. This is another example of Gaudi's Art Nouveau architecture. Like the Sagrada Familia, this building causes passers-by to literally stop in their tracks. The immense limestone facade undulates like ocean waves. Its balconies are adorned with detailed iron work and the entryway is a fanciful vision of tortoise shells.

Another curious feature is the unusual appearance of the chimneys. There are dozens of them, as you will see when you make your way to the rooftop of the building, and most visitors feel as though they have the appearance of sentinels and protectors of the building. Recent restorations to the building have opened the attic, which is now used as a multimedia museum of Gaudi's work, and his influence on Barcelona and architecture around the world.