The medieval settlement included an inner city-citadel on a high rocky plateau, an outer city and unfortified suburbs.

Ditch the spotlight-stealing capitals, embrace the charm of lesser-known destinations, and make this the year of the Second City!

Alongside Sofia, three other Bulgarian cities made the list: Varna, which ranked 213th with an index of 35.7%; Burgas, in 226th place with 33.9%; and Plovdiv, in 235th position. At the other end ...