The mud-brick fortress that Abdul Aziz ibn Saud and his followers captured in 1902 marks the event conventionally dated as the beginning of modern Saudi Arabia. The fort was built in the 1860s in the traditional Najdi style — thick walls of sun-dried brick, watchtowers at the corners, a large central courtyard — and served as the military headquarters of whatever power held Riyadh.
Today the fortress is a museum operated by the Riyadh Municipality. The courtyard contains a functional well, surrounded by painted wooden doors opening into bare rooms that give a clear sense of how the original spaces were used. Upstairs, carved walls and wooden columns support the roof of a majlis — the formal reception room for important visitors. The exhibit covers the history of the fortress itself and the events of 1902 in detail. The original spear tip lodged in the main gate is still there.
Open Saturday to Wednesday, 7:30am–1:30pm; a permit from the nearby museum may be required. Admission is free.