The park's initial were donated by Mrs. Isabella Eleanor Neff, mother of Governor
Pat Morris Neff in 1916. Upon her death in 1921, Governor Neff created the Mother Neff Memorial Park, making it the first state park in Texas. The additional land was deeded to the state in 1934 by private owners; Governor Neff deeded and Mr Frank Smith deeded . The park charges a nominal entry fee for ages 13 and older. Company 817 of the
Civilian Conservation Corps built the park from 1934 to 1938. The company used local materials such as limestone and local hardwoods (oak, elm, juniper, and cottonwood) to build the entrance portals, concession club house, caretaker’s building, pump and drainage systems, fences, and picnic areas. They also built roads, trails and terraced the flood plain. Texas F.A.S. [federally assisted secondary road] 21-B(1) (County Road 314 locally known as Old River Road or Oglesby Neff Park Road) is a length of road built in 1939. The Texas State Highway Department constructed the road using allocated federal funds. The road follows the Leon River for much of its length from the west entrance of the park to
Farm to Market Road 107. Most of Mother Neff Park sits in the flood plain of the Leon River and flooding shut the park down in 1992 and 2007. Flooding in 2015 closed the lower half of the park, and the section is not reopened as of 2026. The park built a new camping loop and visitor center above the
floodplain that opened in 2015. ==Geography==