Mueang Rayong is the capital district (amphoe mueang) of Rayong Province, Thailand. The provincial administration is in Tambon Map Ta Phut. The town of Map Ta Phut is in the western part of Mueang Rayong District. It is the site of the Map Ta Phut Industrial Estate, Thailand's largest petrochemical and heavy industry park. It contributes to Rayong Province's outstanding economic output, but has also become known for scandals involving hazardous waste, industrial accidents, and pollution.