The hillock looming at the southwest end of Santa Eulària was a perfect retreat for the town's citizens during the centuries when Ibiza was plagued by pirate attacks. Crowning its 52m summit is a remarkable fortress-church, with its very own defence tower. There are a couple of interesting museums here, too. The most scenic route up is on the steep stairs from Carrer de Sant Jaume.
You can also walk up to Puig de Missa along an interpretive trail, marked with information boards, that runs from Santa Eulària's seafront promenade to its ajuntament (town hall).