Antoni Gaudí completed the renovation of Casa Batlló in 1906.
Gaudí redesigned the Barcelona house for the industrialist Josep Batlló after Batlló acquired it in 1903. Although the original plan reportedly contemplated demolishing the building, Gaudí instead transformed the existing structure through an extensive renovation carried out from 1904 to 1906.
The work reshaped the main apartment, enlarged the central light well, added floors, and created the distinctive façade with undulating stone, colorful ceramic fragments, mask-like balconies, and a dragon-inspired roofline. The building’s organic appearance earned it the Catalan nickname Casa dels ossos, or “House of Bones.”
The date can be confused with 1904, when Gaudí began designing the project, or with later restoration campaigns. The city also considered Casa Batlló for its annual building award in 1906, but it did not win. Casa Batlló is therefore associated with both the completion of Gaudí’s renovation and the architectural competition of the same year.