Casa Batlló
This apartment building, another of Antoni Gaud's most picturesque designs, was renovated at the turn of the 20th century rather than being built from the ground up. You won't need to have been to Barcelona to recognize the structure's roof, whose tiles resemble a large dragon's scales. Like all of his creations, Casa Batlló's interior and exterior have a sinuous quality with few straight lines and exquisite attention to detail. Consider the noble floor's mushroom-shaped fireplace, which was created as a cozy grotto for couples to warm up in the cold.