Built in 1914, on the promontory of the former Our Lady of Copacabana chapel, the Forte de Copacabana (Copacabana Fort) was one of Rio’s premier defenses against attack. You can still see its original features, including walls up to 12m thick, defended by Krupp cannons. The several floors of exhibits in the fort’s museum, tracing the early days of the Portuguese colony to the mid-19th century, aren’t the most tastefully presented, but the view alone warrants a visit. There’s a lovely café overlooking Copacabana.