Copacabana Fort, or Forte de Copacabana, is a coastal defense fortress built between 1908 and 1914 on the headland at the southern end of Copacabana Beach, where a small chapel to the Virgin of Copacabana once stood. Its reinforced concrete walls and massive Krupp cannons, some capable of firing a shell 23 kilometers out to sea, were built to guard the entrance to Guanabara Bay.
The fort’s coastal artillery was decommissioned in 1987, and the site is now home to the Museu Historico do Exercito, the Brazilian Army History Museum, which displays military history alongside the original cannon emplacements. The fort’s headland position also makes it one of the best vantage points in Rio for photographing the full sweep of Copacabana Beach.
It’s an easy stop at either end of a walk along the Copacabana beachfront promenade, and the small on-site cafe is a popular spot to sit with a view of the surf.