Estonia, Tallinn, Towers in the Old Town.

France, Corsica, Calvi, The Citadel.

France, Corsica, Calvi, View of the Citadel from the harbour.

France, Corsica, Calvi, The Citadel.

Uzbekistan, Bukhara, Outer walls of the Ark Fortress, Registan Square.

Uzbekistan, Bukhara, Outer walls of the Ark Fortress, Registan Square.

Uzbekistan, Bukhara, Entrance, outer walls and viewing gallery of the Ark Fortress, Registan Square.

Uzbekistan, Bukhara, Entrance, outer walls and viewing gallery of the Ark Fortress, Registan Square.

Uzbekistan, Bukhara, Entrance of the Ark Fortress, Registan Square.

Uzbekistan, Khiva, Kunya Ark, also known as Kohna Ark, housing Museum of Ancient Khorezm, Ichan Kala.

Uzbekistam, Khiva, Akshi Bobo, a tower of Kunya Ark, on left, and outer wall of Ichan Kala.

England, West Sussex, Shoreham-by-Sea, Tourist map of old fort ruins next to harbour entrance.