Asen's Fortress in Asenovgrad

You're standing at Asen's Fortress, high on a rocky ridge in Bulgaria's Rhodope Mountains. A couple of kilometres to the north lies the town of Asenovgrad. Now look down: that's the Asenitsa River below you. Whoever held this rock could watch the whole valley. No wonder people have lived up here for so long. The oldest finds go back to the Thracians, and the Romans and Byzantines were here too.