It is the narrowest part of the Malay Peninsula, located in the area of Ban Thap Li, Mamu Sub-district, Kra Buri District, Ranong Province and Sawi District, Chumphon Province, about 545 kilometers on National Highway No. 4, 66 kilometers from the municipality. A replica of the Kra Isthmus, with a distance from the west coast to the east coast, only 50 kilometers wide, this area is considered an important strategic area. that has been of interest since the reign of King Narai the Great In order to dig a canal through until the reign of King Rama IV, France thought of digging the Kra Isthmus to shorten the distance of navigation from the Andaman Sea to the Gulf of Thailand. without having to go around the Malaya Peninsula But due to conflicts of interest with the British owners of the ports in Penang and Singapore, the project had to be suspended.