For the modern visitor it is not difficult to see why Bellinzona's castles managed to hold marauders at bay. Built high up on platforms of rock, they dominate their surroundings like the Alpine peaks that tower behind them.
For centuries, the castles of Castelgrande, Montebello and Sasso Corbaro defended the Ticino valley from invasion, and guarded one of the key routes linking northern and southern Europe.
It is here that the St Gotthard, the Nufenen, the Luckmanier and the San Bernardino passes converge, allowing travellers passage through the Alps. In the Middle Ages the city was also a key crossroads for travellers going from east to west - the busy Greina and the San Jorio routes met here.
Local tour guide, Linda Kohler, says Bellinzona's key position in a narrow valley meant the castles formed a formidable barrier between north and south.
"Many invading forces wishing to enter northern Italy from Switzerland would have been ready to pack their bags and turn back after taking one look at Castelgrande. Being on top of a hill, access was virtually impossible. As the 15th century continued, the fortresses were expanded even further until eventually it became impossible to conquer them."
Castelgrande is in excellent condition, having recently been renovated by the prestigious Ticinese architect, Aurelio Galfetti. The original structure has survived the past 600 years largely intact but sections of the walls have had to be replaced.
Linda Kohler says the people of Bellinzona have mixed feelings about Galfetti's repairs. "I think there were two reactions at the time the work was completed [in 1992]. Most people feel he did a reasonably good job considering the difficulty of marrying modernity with the ancient substance. Others, including myself, think that simply covering a wall in cement, creating quite a stark contrast, isn't quite the right answer."
The site of Castelgrande has been inhabited since pre-historic times. In the 1960s archaeologists unearthed a series of artefacts from the Neolithic and Roman periods. "They found many artefacts dating from the Bronze and Iron Age," says Kohler. "It became clear that there must have been some kind of ancient camp of settlers at this site."
A half-an-hour walk away from Castelgrande is Bellinzona's second historical gem: Montebello castle, which also houses the civic museum with the archaeological remains discovered at Castelgrande. Montebello's most striking feature is its drawbridge covering a deep moat.
The castle offers spectacular views of the St Gotthard pass.
Half a kilometre to the southwest of Bellinzona lies the third and smallest of the three castles: Sasso Corbaro. Like its two big brothers, was built by the Dukes of Milan in the middle of the 14th century.
It has had a chequered history, according to Kohler. "In peacetime, which incidentally was very seldom, the castle was used as a prison. But it wasn't as secure as its architects boasted. In 1494 one prisoner managed to escape."
Indeed Sasso Corbaro seems cursed. Lightning struck the buildings several times and by 1900 it was falling into ruin. It was rescued by massive restoration work in the 20th century, but experts now fear that the repairs have consigned much of its archaeological heritage to oblivion.
Besides the three castles, the valley was defended by a massive wall - the so-called Murata - starting at the western edge of Castelgrande.
In its complete form, the Murata connected the castles and stretched down into Bellinzona, across the river Ticino. It was a bulwark against would-be invaders and provided shelter for Milanese archers and artillery defending the valley.
Marco Molinari, head of Ticino's department for the conservation of historical monuments, says the Murata withstood invasion for centuries, only to fall victim to recent floods.
"The Murata was at the peak of its architectural glory towards the end of the 15th century. The present state of conservation is excellent. Unfortunately floodwaters destroyed the most impressive part of the wall on the West bank of the river Ticino. A landslide in Biasca, some 20 kilometres upstream from Bellinzona, caused a flash flood which broke the wall."
The people of Bellinzona retain a special affection for the Murata and the castles, both because they embody the region's rich architectural heritage, and because of their role as defenders of the region's antecedents.
Molinari sums it up: "In the whole of the Alpine region we have the only testimony to a particular kind of fortification, which completely blocked access to the north and south. In Bellinzona, you can literally see history written on the walls."
by Greg Morsbach