The Fortaleza de Nossa Senhora da Conceição is the oldest building in Maputo, a low square fort of dark stone walls built by the Portuguese in the 1780s on the site of an earlier wooden stockade. It is more interesting historically than aesthetically: the walls are squat, the courtyard small, and the guns on the bastions are decorative rather than impressive.
Inside is a modest military museum — uniforms, weapons, photographs from the colonial wars and the war of independence — and a series of small chapels and barracks rooms. The most arresting object is the tomb of Ngungunyane (Gungunhana) below the chapel. The fort opens 09:00–16:00, with a small entrance fee.