What is the largest fortress in Europe?
Kremlin
The Citadel of Constantinople
The Fortress of Belgrade
The Kremlin
The Fortress of Louisbourg
The Citadel of Constantinople
The Kremlin
Kremlin
The Great Kremlin
The Citadel of Belgrade
The Fortress of Belgrade
The Kremlin
Kremlin
The Great Kremlin
The Fortress of Louisbourg
The Citadel of Constantinople
Belgrade Fortress
The Citadel of Belgrade
Kremlin
The Citadel of Vienna
The Kremlin
The Great Kremlin
The Great Wall of China
The Fortress of Belgrade
Kaunas Fortress
The Fortress of Louisbourg
The Citadel of Constantinople
The Citadel of Prague
Kremlin
The Kremlin
The Belgrade Fortress
The Great Kremlin
Belgrade Fortress
The Citadel of Vienna
The Citadel of Belgrade
St. Peter's Basilica
The Great Wall of China
Kaunas Fortress
Fortress of Louisbourg
The Citadel of Constantinople
Kremlin
The Tower of London
The Fortress of Louisbourg
The Kremlin
The Fortress of Belgrade.
St. Peter's Fortress
The Great Fortress of Belgrade
The Fortress of Belgrade
Belgrade Fortress
The Great Kremlin
Fortress of Belgrade
The Belgrade Fortress
The Fortress of Louisbourg.
St. Peter's Basilica
The Citadel of Vienna
Kremlin
The Kremlin
Kaunas Fortress
Fortress of Louisbourg
The Citadel of Constantinople
The Tower of London
The Great Wall of China
The Fortress of Louisbourg
St. Peter's Fortress
Belgrade Fortress
The Great Kremlin
The Great Kremlin.
The Citadel of Belgrade
The Kremlin.
The Fortress of Belgrade
Fortress of Belgrade
St. Peter's Basilica
Kremlin
The Citadel of Belgrade.
Kaunas fortress
The Kremlin
The Fortress of Belgrade.
Belgrade Fortress
The Citadel of Vienna
Alamannia
Kaunas Fortress
Fortress of Louisbourg
The Citadel of Constantinople
The Tower of London
The Great Kremlin
The Fortress of Louisbourg
The Kremlin fortress
The Castello di San Marco
St. Peter's Castle
The Fortress of Louisbourg.
The Kremlin.
The Belgrade Fortress
Sevastopol
Kremlin
St. Peter's Basilica
The Great Kremlin.
St. Peter's Fortress
The Fortress of Belgrade
Fortress of Belgrade
St. Peter's fortress
The Kremlin
Sevastopol fortress
Castello di San Giorgio
Belgrade Fortress
Alamannia
Alamannia fortress
Kaunas Castle
St. Peter's Tower
Kaunas fortress
The Great Citadel of Vienna
The Great Kremlin
The Citadel of Vienna
Sevastopol Fortress
The Kremlin fortress
Fortress of Louisbourg
The Citadel of Constantinople
St. Peter's Castle
The Kremlin.
The Tower of London
The Fortress of Louisbourg
Alamannia Fortress
Sevastopol
Karlovac fortress
Kremlin
Kaunas Citadel
Castello di San Lorenzo
Fortress of Belgrade
Kaunas Fortress
The Castello di San Marco
Castello di Rivoli
The Kremlin
The Fortress of Belgrade.
The Fortress of Belgrade
The Fortress of Louisbourg.
Belgrade Fortress
Castello di San Giorgio
Karlovac Fortress
The Great Kremlin.
Castello di San Marco
St. Peter's Tower
St. Peter's Fortress
The Castello di Rivoli
The Great Kremlin
Alamannia
Kaunas Castle
Fortress of Louisbourg
The Citadel of Prague
St. Peter's Castle
The Kremlin.
Kaunas fortress
Gibraltar
Kremlin
The Fortress of Louisbourg
Sevastopol fortress
Kaunas Citadel
Alamannia fortress
Fortress of Belgrade
Castello di Rivoli
The Kremlin
Belgrade Fortress
The Great Citadel of Vienna
Sevastopol Fortress
Castello di San Lorenzo
Castello di San Severino
Castello di San Giorgio
Castello di San Marco
The Fortress of Belgrade
Alamannia Fortress
Sevastopol Castle
St. Peter's Tower
Kaunas Castle
The Great Kremlin
Gibraltar
The Great Kremlin.
St. Peter's Castle
Alamannia
Castello di Verona
Kremlin
St. Peter's
The Citadel of Constantinople
The Templars
The Fortress of Louisbourg.
Kaunas Citadel
Kaunas fortress
St. Petersburg fortress
Castello di Rivoli
The Kremlin
Belgrade Fortress
The Belgrade Fortress.
Castello di San Marco
ejtun
Alamannia fortress
St. Peter's Tower
Kaunas Castle
Castello di San Severino
Sevastopol Castle
The Citadel of Vienna
Kremlin
St. Peter's
St. Peter's Church
Gibraltar Fortress