Everyone who talks about the Tara canyon quotes the same number, and it holds up: up to about 1,300 metres from rim to river, which makes it among the deepest gorges in Europe and the deepest in this part of the world. The Tara runs for roughly eighty kilometres, cuts through the north of Montenegro on its way to join the Piva and become the Drina, and the whole thing sits inside a protected biosphere reserve. From the road you see the green end of it, black pine forest dropping into a thin turquoise line a very long way down.
The place most riders stop is the Đurđevića Tara Bridge, a concrete arch of five spans that carries the road about 170 metres above the water. It was finished in 1940, and its story is a sad one: during the Second World War its designer was made to take part in blowing up one of its arches to slow an Italian advance, and the bridge was patched up afterwards. Today it is a viewpoint, a photograph and a zip line, in that order of seriousness. Park off the carriageway, walk onto the bridge, and look down the canyon in both directions. In summer there are rafting trips below, and the little rafts look like confetti.
The roads on either side are what you came for, wide, fast bends through forest and open hayfields, with Durmitor's grey teeth rising to the south. Žabljak, fourteen kilometres away, is the base for the mountains, and Pljevlja to the north is the nearest proper town with services, so if the tank is low that is where the choice is larger. Traffic is light apart from tour coaches and the occasional herd on the tarmac.
Weather changes fast at this height. A morning of hard blue sky can turn to rain by afternoon, and the temperature at the bridge in June can be a long way below what you left in Podgorica. Take a layer, take water, and give the hairpins on the canyon road their full attention. The best light for riding is the first two hours after sunrise, before the shadows fill the gorge.