Ulitsa Ivan Vazov leads directly from the museum to the medieval fortress, Tsarevets. A successful rebellion against Byzantium was mounted from this citadel in 1185, and Tsarevets remained the centre of Bulgarian power until 1393, when, after a three-month siege, it fell to the Turks. The partially restored fortress is entered via the Asenova Gate halfway along the western ramparts. To the right, paths lead round to Baldwin’s Tower, where Baldwin of Flanders, the so-called Latin Emperor of Byzantium, was incarcerated by Tsar Kaloyan. Visitors can climb up to the parapet of the fully renovated tower for sweeping views of the town.

Don’t miss the dramatic 20-minute Tsarevets Sound and Light show held most evenings during the summer – it’s free on public holidays, but on other days you’ll have to wait for a large group to fork out for it.