It's a palace of music and concerts are held here, but it also attracts visitors for its modernist tilework and stained glass. The interior of the building is beautiful and crowned by a fantastic (and huge) inverted dome of stained glass in the main auditorium. Guided tours are every 30 minutes during the day - just wait outside the door until they let you in - it's worth it.
Carrer de Sant Pere Mes Alt
You can also book tickets in advance for tours at the souvenir shop across from the Palau - essential to book as they are very popular. In Feb 2006 we paid about €16 for two people on the English tour - worth every cent.