Birthplace of St Francis Xavier (Navarre’s most famous saint, born here in 1506) and now bearing his name, this fortress was partially dismantled in 1516 by Cardinal Cisneros, Regent during Charles V’s minority. Inside are the Hall of Arms, the Great Hall (17C furniture), and the saint’s bedroom. It adjoins the keep, or Tower of San Miguel (fine view). The Chapel of Santo Cristo has a 13C walnut Christ figure and a 15C Dance of Death fresco.