Casa Milà

Gaudí’s Casa Milà is arguably the most controversial residential house in Spain. The building is a construction of concrete and iron and has neither supporting nor retaining walls.
 They say that there isn't a single straight line and no right angle in the whole building. The enormous corner house actually consists of two houses and two inner courtyards, which provide for a good construction for natural light and air ventilation.
 The creative nature of Gaudí generated expressionistic dimensions when creating this piece of architecture.
Due to its wavelike facade it is also known as “La Pedera” (quarry). The facade of limestone appears wavelike and conjures the image of a rock face.