Casa Batlló is a key feature in the architecture of modernist Barcelona. It was built by Antoni Gaudí between 1904 and 1906 having been commissioned by the textile industrialist Josep Batlló. It seems that the goal of the designer was to avoid straight lines completely. Much of the façade is decorated with a mosaic made of broken ceramic tiles (trencadís) that starts in shades of golden orange moving into greenish blues. The roof is arched and was likened to the back of a dragon or dinosaur. A common theory about the building is that the rounded feature to the left of centre, terminating at the top in a turret and cross, represents the lance of Saint George (patron saint of Catalonia, Gaudi's home), which has been plunged into the back of the dragon.