Fort Copacabana Fort Copacabana ( Brazilian Portuguese : " Forte de Copacabana " , ) is a military base at the south end of the beach that defines the district of Copacabana , Rio de Janeiro . The base is open to the public and contains the " Museu Histórico do Exército " ( Museum of the History of the Army ) and a coastal defense fort that is the actual Fort Copacabana . History . The fort is built on a headland that originally contained a small chapel holding a replica of the Virgen de Copacabana , the patron saint of Bolivia . In 1908 the Brazilian army started to build a modern coastal defense fort on the headland to protect both the beach of Copacabana and the entrance to the harbour of Rio de Janeiro . The fort was completed in 1914 . It consists of two cupolas , one holding a pair of 305mm ( 12 inch ) Krupp cannons , and the other a pair of 190mm ( 7 . 5 inch ) Krupp cannons . The name of the cupola with the 305mm guns is " Duque de Caxias " , and the guns are named " Barroso " and " Osório " . This cupola is behind and above that of the 190mm guns so that it can fire over them . The 305mm Krupp guns could fire a shell of some 445 kg a distance of up to 23 km . The name of the cupola with the 190mm guns is " André Vidal " . These guns could fire from 200meters to 18 . 2 km . The fort also has two small casemate s on the flanks , each of which held a 75mm quick - firing gun with an 180° traverse and a range of 7 km . Unlike the large Krupp guns , these 75mm guns are no longer in place . The north casemate is named " Antônio João " and the south casemate is named " Ricardo Franco " . On 5 July 1922 , the fort was the centre point of the 18 of the Copacabana Fort revolt . It was the first revolt of the " tenentista " movement , in the context of the Brazilian Old Republic . The rebellious officers turned the fort ' s guns on Rio de Janeiro . To suppress the revolt , the government brought up two battleships , the " São Paulo " and the " Minas Geraes " . On 6 July " São Paulo " bombarded the fort , firing five salvos and obtaining at least two hits ; the fort surrendered half an hour later . " Minas Geraes " did not fire . Brazil disbanded its coastal defense artillery branch in 1987 . At that time the fort was deactivated , at least as far as the its role as a coastal artillery post was concerned . Visiting the fort . The hours for the Museum are 10 am to 6 pm and the fort are 10 am to 8 pm , Tuesday to Sunday and holidays . Admission for adults is R $ 4 per adult ; there are discounts and free tours for the elderly and children . At the entrance to the base there is a guard in the uniform that was current when the fort was opened in 1914 . Museum & artillery park . The museum has several exhibits focusing on different periods and events in the history of the army in Brazil . Regrettably , the Brazilian Expeditionary Force s participation in the Italian campaign in World War II gets only limited treatment , and Brazil ' s involvement in World War I receives no treatment . Outside the museum there are several artillery pieces from the late 19th and early 20th Centuries . For instance , one field piece is a 5 - barrel quick - firing gun , each barrel being of 37mm . Brazil purchased this Hotchkiss revolving cannon , in 1876 . Another field piece is a British - made Vickers - Armstrong Mark XIX 6 " ( 152 . 4mm ) gun , made in 1918 . Brazil purchased this piece in 1940 for use in coastal defense . There are also three 75mm Schneider M1919 mountain guns . 2016 Summer Olympics . For the 2016 Summer Olympics , the fort is scheduled to host the marathon swimming and triathlon events . External links . city city