Bellinzona is in northern Ticino. Historically, it was on the main route between central Switzerland and northern Italy via the St Gotthard pass, and in the 15th century (when the Swiss Confederation was an aggressive neighbour) three castles - Castelgrande, Montebello and Sasso Corbaro - were built by the Dukes of Milan to defend the area against the invaders. These three castles are well preserved, and are the main tourist attraction of Bellinzona today.
There is an overview of the history here.
On to the pictures. Click on the little images to enlarge them.