St. Helena is one of the most isolated inhabited islands in the world (lacking an airport) and there are a vast number of plant and animal species unique to the island. This isolation has resulted in numerous interesting species that makethe island an ecological treasure. Of the biological diversity that St. Helena presents are some 400 distinctive invertebrates and 65 plant species found nowhere else in the world. The island used to have 6 endemic bird species yet today there is only the wire bird left. This is also the island's national bird. A turtle brought to the island from the Seychelles in 1882 with the name Jonathan is said to be the last living individual of its species. The few mammals found in St. Helena have all been introduced to the island.

A rough coast line with steep cliffs surrounds a green and lush inland. The highest point on the island is 823 m and is located in the Diana's Peak National Park where also most of the endemic species are found. Scattered in the nature are also a number of old ruins of historic origin, some from the 15th century. Since the island is so small and distances short we endeavor to explore most of it on foot.