Cannon Ball Concretions in the badlands, Theodore Roosevelt National Park, North Dakota, United States of America, North America

Palais du Prince, Monaco, Cote d'Azur, Europe

The Tsar Cannon, Kremlin, Moscow, Russia, Europe

The Tsar Cannon, Kremlin, Moscow, Russia, Europe

Old guns pointed towards the sea on the roof of Walmer Castle, 1540, Walmer, Deal, Kent, England, United Kingdom, Europe

Historic cannon balls, welded together, Fort Christiansvaert, Christiansted, St. Croix island, U.S. Virgin Islands, United States

Cannon balls, El Morro, Morro Castle, Santiago de Cuba, historic district, Cuba, Caribbean, Central America

Close-up of a cannon and cannon balls, Castillo De San Marcos National Monument, St. Augustine, Florida, USA

Stack of cannon balls on castle roof, Castillo San Cristobal, San Juan, Puerto Rico, San Juan, Puerto Rico, Puerto Rico