This is where Spain's story of reconquest is told, at least the way it is told in Asturias. A few kilometres up the road at Covadonga, the local lord Pelayo is said to have beaten a Muslim force around 722, an event that became the founding legend of the Kingdom of Asturias, and Cangas de Onís was that kingdom's first capital. So a small town of about six thousand people carries rather a lot of history, and it shows in the Roman Bridge, which is actually medieval, with its high single arch over the Sella and a cross hanging beneath it.
For a rider it is the gateway to the Picos de Europa, and the place from which most loops begin. The altitude is only 80 metres, and the limestone massif rises behind it almost straight out of green farmland, reaching over two thousand metres within a short distance of the coast. The roads that climb from here are tight, rain-slicked in the morning and often cloud-capped, and the climb to the Lakes of Covadonga is steep, narrow and technical, with cattle and sometimes cyclists in the way. Take it early or late if you can, as the tour buses are controlled in summer.
Towns like this are made for stops. Cangas has plenty of fuel, supermarkets and bars, and you should try the local cider, poured from a height in the traditional style, and the strong blue cheeses of the region, the best known being Cabrales. Fabada, a bean stew with chorizo and morcilla, is the standard answer to a cold day in the mountains. The Sella river runs right past the town, and each August the famous canoe descent from Arriondas finishes near here, with a festival atmosphere.
Weather is the thing to watch. Atlantic cloud can sit on the range for days and then clear in an hour, so pack a rain layer even if the morning looks promising, and carry on if the clouds rise, because the views back toward the sea are extraordinary.