Robert Allerton Park is a 1,517-acre estate landscape near Monticello, Illinois, created by Robert Henry Allerton after he returned from study in Europe in 1897 and spent decades transforming prairie and woodland along the upper Sangamon River into an elaborate designed landscape. Centered on a Georgian Revival house, it is known for formal gardens, sculpture, and a preserved natural area, including the Fu Dog Garden, Brick Walled Garden, Peony Garden, and Chinese Maze Garden. In 1946 Allerton deeded the larger estate to the University of Illinois, and it later became both a public park and conference center, recognized for its cultural and natural significance.