The Maritime Heritage Trail takes 'hikers' through one of the only trails of its kind in the USA. If you've ever wanted to explore a sunken ship, this may well be the best opportunity in the country. Six are located within the park grounds; the trail experience involves taking visitors out, by boat, to the site of the wrecks where they can swim and explore among derelict vessels and clouds of fish – there are even waterproof information site cards placed among the ships. Five of the vessels are suited for scuba divers, but one, the Mandalay, a lovely two-masted schooner that sank in 1966, can be accessed by snorkelers.