Photo: Jose Ligero Loarte, CC BY-SA 4.0 Free historic sites in Sofia
Photo: Jose Ligero Loarte, CC BY-SA 4.0 
Photo: No machine-readable author provided. Preslav~commonswiki assumed (based on copyright claims)., Public domain Rotunda of St. George
Free, alwaysAncient Serdica
Free, always
Photo: Stolichanin, CC BY-SA 4.0 St Nedelya Church
Free, always
Photo: MrPanyGoff, CC BY-SA 3.0 Banya Bashi Mosque
Free, always
Photo: Stolichanin, CC BY-SA 4.0 Vitosha Boulevard
Free, always
Photo: Deensel, CC BY 2.0 National Palace of Culture
Free, always
Photo: SiefkinDR, Public domain