Sagrada Familia, still under construction
Spain, Barcelona, Oct. 2009
The Sagrada Familia is considered the masterwork of the renowned Catalan architect Antoni Gaudi (1852 - 1926). The project's vast scale and idiosyncratic design have made it one of Barcelona's (and Spain's) top tourist attractions for many years. It is a massive, privately-funded Roman Catholic church that has been under construction since 1882 and is not expected to be complete until at least 2026:
http://en.wikipedia.org/wiki/Sagrada_Fam%C3%ADlia