It is a reservoir used for consumption. within the area of Khao Yai National Park and to be a source of water for wildlife It was built by Mr. Boonrueang Saisorn, the first head of Khao Yai National Park in 1981. During this construction period, Mr. Boonrueang returned to the position of Superintendent of the Park in the second term, originally known as the Mo Singto Reservoir. It is called by the name of Khao Mo Singto in front of the reservoir, which is shaped like a lion, but later in 2007 it was renamed Sai Sorn Reservoir in honor of Mr. Boonrueang Sai Sorn, the first former head of Khao Yai National Park. who contributed to the pioneering in the establishment of the park And don't let common people mistakenly think that there are lions in Khao Yai National Park.