When we would walk toward the Cathedral we could see what looked like a fortress up on the hill. Looking it up, it was called Bellver Castle, a 1300s castle built by King Jaime II of Mallorca, used as a prison for two centuries but now housing a History Museum. It also apparently had a breathtaking view of Palma. We looked at going there by public bus but we couldn't really understand the directions. Plus, apparently the bus let you off at the bottom of the hill and it was a 15-minute climb to get to the Castle. So we opted to pay for the red Hop On, Hop Off double decker bus that we had seen around Palma for the past few days. And we were quite glad we did. We rode the whole route and saw some great Palma neighborhoods as well as getting off at two places--Puebla Espanol and the Castle--that were so interesting to visit. We actually got off at the Puebla Espanol by mistake, thinking it was the Castle but golly it was gorgeous. I haven't been able to find much information ...