Located 2300 kilometres northwest of Perth, Western Australia, Christmas Island is at latitude 10°25'S and longitude 105°43'E. Christmas Island covers 135 square kilometres, of which approximately 60 per cent has been declared as National Parks.
The island is the summit of a submarine mountain, which rises steeply from sea level to a central plateau. The plateau reaches heights of up to 361 metres and consists mainly of limestone and layers of volcanic rock. Surrounding the island is a narrow tropical reef which plunges steeply to the ocean floor. Within 20 metres of the shoreline, you can find some of the steepest drop-offs in the world reaching a depth of about 500 metres within about 200 metres beyond the edge of the reef. Combined with the diverse array of aquatic wildlife making its home in the reef, these undersea formations make diving around Christmas Island very popular.
Christmas Island is famous also for red crabs and their migration across the island, which often causes havoc for the residents by blocking roads. This abundance of land crabs is not matched by any other island and has been described as one of the wonders of the natural world. More than 20 species of terrestrial and intertidal crabs have been described including the huge robber crabs, or coconut crabs, which are capable of opening coconuts with their strong claws and eating the contents.
Mining of phosphate has been carried out on Christmas Island since the late 1800s and remains a large contributor to the island's economy, although the focus is moving more towards tourism and related industries. The phosphate is derived from bird droppings.