The Casa Batlló is a work of the famous Catalan architect Antoni Gaudí which rises in Barcelona, Spain, at number 43 of Passeig de Gràcia. This house-museum occupies a total of 4300 m2, with 450 m2 of floor area per floor, and has a height of 32 metres. Considered one of the famous architect's most original creations, the building was declared a UNESCO World Heritage Site in 2005.