Largo da Oliveira is named after a centuries-old olive tree planted on the same site. It is surrounded by a group of houses typical of northern Portugal, and is an ideal starting point for a walking tour of the city streets. The square itself also has a number of interesting features; On the eastern side is a strange Gothic mausoleum built during the reign of de Afonso IV to commemorate the Battle of Salado, where Portuguese and Castilian forces together defeated the Moroccan army from Granada in 1340.