Prince Alexander I Square (Bulgarian: площад Княз Александър I, Ploshtad Knyaz Aleksandar I), often called simply Battenberg Square (площад Батенберг) is the largest square of Sofia, the capital of Bulgaria. It is named after Alexander Joseph of Battenberg (Alexander I of Bulgaria), the first prince of modern Bulgaria. During the Communist rule of Bulgaria, the square was named September 9th Square, after a coup on September 9, 1944, made the country a Communist state.
Source: Wikipedia
