Đavolja Varoš, the Devil's Town, is a ravine of about two hundred earth towers in the Toplica district of southern Serbia, on the slopes of Mount Radan, each column of volcanic ash and grit standing only as long as the hard stone capping it keeps the rain off, and it is walked on a boardwalk down among the towers and seen from a viewpoint on the rim, with two springs of acid water at the bottom. The towers are between two and fifteen metres tall, formed as the rain washed the soft volcanic debris away from around the stones that now sit on their tops, and when a cap falls the tower melts in a few seasons while new ones rise behind it; from the rim they resolve into dozens of capped columns packed into one gully, all leaning down the slope the same way, and the trail drops between them close enough to see their grain, ash, grit and embedded pebbles with a dark slab balanced on top. The legend has a wedding party turned to stone by God for marrying a brother and sister, and an older telling drops the wedding altogether, since the towers are devils shaken off by people who slept a night beside the church ruins.
Below the towers the Devil's Water seeps out as acid rather than mineral water, at a pH of 1.5 and carrying fifteen grams of dissolved minerals in every litre, sour enough that the ground around it stays bare, and a few steps away the Red Spring runs rust red across its bed. The tunnels beneath the gully were cut by Saxon miners brought into Serbia in the thirteenth century to open its ore, one traced for 800 metres, and a small timber church of Sveta Petka with a painted icon on its gable stands above the towers. Through October the oak and beech on the rim turn copper around the bare white-and-ochre towers. Đavolja Varoš is a crowd of stone-capped columns, and every one is waiting for its hat to fall.