Thailand has to major rivers, there two major rivers are Chao Phraya and the Mekong. There are three main features in Thailand's terrain: high mountains, a central plain and an upland plateau. The cental plain is a lowland dried by the Chao Phraya River and its tributaries. Thailand has four major regions: northern, central, eastern, and peninsular. Thailand lies enterily within the topics and has warm to hot weather all year.