Mercury is a strange thing to build a town on. In 1490, according to the story, a local cooper was soaking a tub in a spring when he noticed a gleaming liquid metal in the bottom, and the find was the start of one of the biggest mercury mines in the world. Idrija, a small town in a narrow valley in western Slovenia, became rich on the metal, which was used for medicine, mirrors, gold extraction and later for gunpowder detonators. The mine ran for about five hundred years until it was closed in 1994, and together with the mine at Almaden in Spain, Idrija was inscribed as a World Heritage site in 2012.
The old town is a compact cluster of tall houses and miners' buildings around the river, dominated by Gewerkenegg Castle, a sturdy sixteenth-century building that was once the mine's administration and storehouse and now houses the municipal museum. Part of the mine is open for visits, and you can go down a tunnel in a helmet and walk through the old workings, which include a small chapel and a Miner's House. The town also has a lace-making tradition that began in the seventeenth century, when miners' wives made lace to earn money, and the Idrija School of Lace still teaches the craft. The local dish, Idrijski zlikrofi, are small dumplings filled with potato and herbs, protected by a European label, and you can try them in almost any local restaurant.
The roads to Idrija are one of its charms. From Ljubljana, the route runs through Vrhnika and Logatec, then climbs into forested hills, and the road down into the valley winds through steep woods with tight curves and views across the narrow valley. The surface is generally good, but traffic can be heavy with trucks and commuters, and there are speed cameras. From Idrija the roads climb to the Cerkno hills and the Idrijca valley, with curves, hairpins and scenery that Slovenian riders love. Spring and autumn are the best times, when the beech forest is bright green or burnt orange. Winter brings ice and snow.
Idrija has about six thousand people, so fuel, shops, restaurants and rooms are all easy to find. The Krokar forest reserve, on the ride, is a rare patch of virgin beech and fir woodland in the Kocevje region, wild and quiet, and a world away from the mine.