Bellinzona, Switzerland - Castelgrande and the Cathedral. The site of the Castelgrande has been fortified since at least the late 1st Century BC (until the 13th Century it was the only fortification in Bellinzona). During its history the castle has been known as the 'Stronghold' (before the 13th Century), the 'Old Castle' in the 14?15th Centuries, 'Uri Castle' after 1506 and 'Saint Michael's Castle' from 1818.