Nearly 20 percent of Aruba is protected land. This sprawling national park, measuring 33 square kilometers (13 square miles), encompasses lava fields, limestone terrain, a small beach and a desertlike landscape, all crisscrossed with a series of hiking trails. Paths lead to gold mine ruins, former plantation remnants and petroglyphs by the island's native Arawak people. Wildlife include two species of snakes endemic only here, as well as bats, lizards and myriad birds. The local island donkey is a common sighting.