BG54 - The Roussensky Lom National Park (1984)

Courtesy of Lilia from Bulgaria

BG5936 - Vratsa Karst Nature Reserve (2011)

Courtesy of Lilia from Bulgaria

BG45 - The Magoura cave with drawings from the bronze age (1984)

Courtesy of Lilia from Bulgaria

BG1948 - The Ancient Plovdiv (2004)

Courtesy of Childish from postcrossing forum

BG50 - The town of Melnik and the Rozhen Monastery (1984)

Courtesy of Childish from postcrossing forum

BG5640 - Rocks of Belogradchik (2011)

Courtesy of Childish from postcrossing forum

BG49 - The Bachkovo Monastery (1984)

Courtesy of Childish from postcrossing forum