The central region is the country's most fertile land on rice growing. Central Thailand, the basin of the Chao Phraya River, is a lush, fertile valley. It is the richest and most extensive rice-producing area in the country and has often been called the "Rice Bowl of Asia". Paddy is the principal raw material for the production of parboiled rice. Due to an abundant water supply and consistent source of paddy in Thailand, more than 100 parboiled rice mills are spread throughout the central region, the production of premium quality parboiled rice in Thailand is constant year round. Thailand is now the world's largest supplier for Alesie Parboiled Rice.