Casa Batllo (World Heritage Site) - One of 2 houses by Gaudí in Barcelona that can be toured. truly amazing and worth the visit. go in the mornings, before the site gets crowded with architecture students.
This beautiful Arc de Triomf was built for the 1888 Barcelona Universal Exposition, which took place at the Parc de la Ciutadella. The Arc de Triomf, situated at the end of a wide promenade, served as the exposition's main entrance.