WebUrbanist ran an article today called Starry Knights: 14 Stellar Star-Shaped Fortresses which did not include our beloved castle in Cape Town. Here is a picture I grabbed from Google Maps.
From Wikipedia:
Built by the Dutch East India Company between 1666 and 1679, the Castle is the oldest building in South Africa. It replaced an older fort called the Fort de Goede Hoop, which was made out of clay and timber and built in 1652 by Jan van Riebeeck upon his arrival at the Cape.
The purpose of both were to act as a replenishment station for ships
passing the treacherous coast around the Cape on long voyages between
the Netherlands and the Dutch East Indies.