Museo Guggenheim, Bilbao
Source: Blogspot, http://2.bp.blogspot.com/_svAyYhspKJw/S8_9yK0Q1NI/AAAAAAAAFt8/HLywzfD7P-Q/s1600/223-126-guggenheim-large.jpg
Designed by architect Frank Gehry and opened in 1997, the Bilbao Guggenheim Museum is considered one of the most beautiful buildings in the world. It stands along the Nervion River and is constructed of titanium blocks, stone and glass all interconnected and irregularly shaped. According to Gehry, the stunning curves are meant to reflect the lights.
Source: CityKnown, http://www.cityknown.com/MainPhotos/007/Attractions/2948884476551370.jpg
Source: Wikimedia, http://upload.wikimedia.org/wikipedia/commons/d/de/Guggenheim-bilbao-jan05.jpg