The best-preserved medieval fortress in Bulgaria, sitting directly on the south bank of the Danube. Foundations were laid in the 10th century on top of an earlier Roman fort, expanded under the Second Bulgarian Empire in the 13th and 14th centuries, and again under the Ottomans. Two concentric walls of stone enclose a parade ground and four corner towers; you can climb three of them for views over the river to Romania.
The interior is sparsely furnished — some replica weapons and a small museum display — but the appeal is the structure itself. Unlike many Bulgarian fortresses Baba Vida was never blown up; it surrendered intact in 1885 and was used as a barracks until the 1950s. Combined with a walk along the riverside park immediately outside the walls, allow about two hours.