saucer-shaped tableland of northeastern Thailand. It occupies 60,000 square miles (155,000 square km), is situated 300–650 feet (90–200 m) above sea level, and tilts southeastward. The plateau is drained by the Chi and Mun rivers and is bounded by the Mekong River (north and east on the Laos border), the Phetchabun and Phang Hoei ranges (west), and the Phanom Dong Rak Range (south). The interior has low hills and small lakes. The plateau's impermeable soils are flooded during the rainy season (April–November) and parched during the dry season. The inhabitants raise cattle, horses, and pigs and cultivate cotton, rice, peanuts (groundnuts), corn (maize), and hemp. The plateau includes the major towns of Nong Khai, Khon Kaen, Nakhon Ratchasima, and Ubon Ratchathani, all of which are linked to Bangkok by rail.