Palau Baró de Quadras

• 50-minute Friday tours, with the 4 PM slot in English, a manageable length for kids
• Beast-covered facade by sculptor Eusebi Arnau, with dragons, knights, and gargoyles to spot before you go in
• Two buildings in one: a Gothic palace from Diagonal, a curvy apartment block from the back street

This palace has two different faces: a Gothic-style front crusted with gargoyles on Avinguda Diagonal and a curvy Modernista apartment block behind. Josep Puig i Cadafalch, the architect of Casa Amatller, rebuilt it in 1904 for the Baró de Quadras, and sculptor Eusebi Arnau packed the facade with dragons, knights, and improbable beasts that make a great spotting game. Now the Institut Ramon Llull's headquarters, it opens for 50-minute guided tours on Fridays.