The Bellinzona site consists of a group of fortifications grouped around the castle of Castelgrande, which stands on a rocky peak looking out over the entire Ticino valley. Running from the castle, a series of fortified walls protect the ancient town and block the passage through the valley. A second castle (Montebello) forms an integral part of the fortifications, while a third but separate castle (Sasso Corbaro) was built on an isolated rocky promontory south-east of the other fortifications.

Źródło: World Heritage Convention
http://whc.unesco.org/en/list/884