What is a province capital in southern Vietnam that is between the province capitals of Rach Gia and Cao Lanh?

Rạch Giá is the capital of Kiên Giang, in southwestern Vietnam. Cao Lãnh is the capital of Đồng Tháp, in the same Mekong Delta Region. The 'provinces' in Vietnam are technically called districts. So, the districts between Kiên Giang and Đồng Tháp are Cần Thơ and An Giang. Their capitals of these districts are Cần Thơ and Long Xuyen.