Bergamo is two cities: the busy modern town on the plain, and the Città Alta on the hill above, enclosed by massive walls built by the Republic of Venice between 1561 and 1588. Bergamo was then the westernmost outpost of Venice's mainland territory, facing the Spanish-ruled Duchy of Milan, and the walls, more than five kilometres long, were designed to withstand artillery, with bastions, platforms and gates. They were never seriously tested in battle, which is why they are so well preserved. In 2017 UNESCO listed them, together with other Venetian fortifications in Italy, Croatia and Montenegro, as the Venetian Works of Defence.
The upper town is a joy to explore on foot, a compact maze of medieval and Renaissance streets, with the Piazza Vecchia at its heart, the Colleoni Chapel with its multicoloured marble facade, and the Basilica of Santa Maria Maggiore. The walls themselves are now a tree-lined promenade, with views over the plain on clear days as far as the Apennines. You reach the upper town by funicular from the lower town, or on foot along steep, cobbled lanes; vehicle access is restricted, so leave the bike below.
Bergamo has its own food traditions: casoncelli, stuffed pasta with butter and sage, polenta in every form, and a sweet called polenta e osei, a yellow cake shaped like a dome with chocolate birds on top. The local cheeses, from the valleys above, include Taleggio and Branzi.
The riding from Bergamo is outstanding. North of the city, the valleys of the Brembo and the Serio cut deep into the Bergamo Alps. The Val Brembana leads to San Pellegrino Terme, the spa town famous for its mineral water, with a Belle Époque casino and grand hotels, and then climbs towards the passes of the Orobie. The Val Seriana leads to Clusone and the Presolana pass, a classic climb with views of the limestone peaks. Lake Iseo, to the east, has roads along its shores with tunnels and bends, and the island of Monte Isola in the middle. The roads can be busy on weekends with Milanese heading for the mountains.
Bergamo has fuel and every service, and the airport at Orio al Serio is close if you are flying in to rent a bike. The best seasons are spring and autumn; summer in the plain is hot and humid.