Ban Thi is the northernmost district of Lamphun province, northern Thailand. The district is named after the Thi River, and literally mean…Ban Thi is the northernmost district of Lamphun province, northern Thailand. The district is named after the Thi River, and literally means 'Thi village'. The minor district Ban Thi was established on 1 April 1990, when two tambons were split off from Mueang Lamphun district. It was upgraded to a full district on 7 September 1995.