Bellinzona's three castles are listed as UNESCO World Heritage sites and are well worth exploring. Bellinzona was an important stronghold as the meeting point of three important north-south routes over the alpine passes of St. Gotthard, San Bernardino, and Lucomagno.

 All three could, in the past, be closed by a barrier across the road at Bellinzona, giving it a strategic position for centuries. The three castles that still dominate the town are among the most important examples of medieval defensive architecture in the Alps.