The country consists of two main islands, Trinidad (1,864 sq mi/4,828 sq km) and Tobago (116 sq mi/300 sq km), and their small neighboring islands. Lying just north of the Orinoco River delta in Venezuela, Trinidad is largely flat or undulating except for a range of low mountains (the highest point is Mt. Aripo, 3,085 ft/940 m) in the north. Pitch Lake, in the southwest, is the world's largest (114 acres/46 hectares) basin of natural asphalt. Tobago, just NE of Trinidad, is the exposed top of a mountain ridge (maximum height 2,000 ft/610 m) that is densely forested with large reserves of hardwoods. The climate of both islands is warm and humid, and rainfall (from June to Dec.) is abundant, particularly where the trade winds sweep in over the eastern coasts. The population is mainly of South Asian or African descent (40% each), with a mixed-race minority. English is the official language, but Hindi, French, Spanish, and Chinese are also spoken. There are many religious groups, including Roman Catholic, Anglican, and other Christian churches, Hindus and Muslims.