Subirach's Facade of the Sagrada Familia
This isn't a great picture, but this is the other side of the Sagrada Familia. I really like it, he uses a lot of negative space and solid lines without too much detail. There is also a cool detail that I didn't get a picture of which is a square divided into 4x4 of smaller square with different numbers. No matter how you add them, take any four of the numbers and they add up to 33, Jesus's age at his death.