Named for the 15th-century Portuguese navigator, the Bartolomeu Dias Museum Complex concentrates on the early history of Mossel Bay, when it was a regular stopover for Portuguese mariners en route to India from Europe. The most popular exhibit is the full-size (340-foot-long) replica of Dias's ship (a caravel), which was sailed to Mossel Bay from Lisbon as part of the quincentenary celebrations in 1988. If you pay the extra fee to board it, you'll find it all pretty authentic, except for the modern galley and heads. Also here is the Post Office Tree. In the 15th century a few sailors decided that the tree—then a lone tree on a deserted beach on an unexplored coast—stood out sufficiently and left some letters here in an old boot, under a stone, in the hope they would be found and delivered. They were. Pop a postcard into the shoe-shape mailbox and see if the service is still as good. Your mail will arrive with a special postmark.