Built by the Dutch between 1666 and 1679 to defend Cape Town, this stone-walled pentagonal castle remains the headquarters for the Western Cape military command. There are free guided tours of the site (11am, noon and 2pm Monday to Saturday), and don’t miss climbing up to the bastions for an elevated view of the castle’s layout and across to Grand Parade.
The Military Museum is interesting, as are the displays of antiques and decorative arts in the William Fehr Collection .