Fall Mountain State Forest is a New Hampshire state reservation managed by the Department of Resource and Economic Development. The state accepted the 948.5-acre property located in the towns of Charlestown and Langdon as a gift from The Nature Conservancy in 2005. The Nature Conservancy acquired the property to protect the habitat of the federally endangered Northeastern bulrush and currently holds an easement on the property. Some acquisition funds were provided by the Land and Community Heritage Investment Program and the Cooperative Endangered Species Conservation Fund; LCHIP holds an Executory Interest, and USFWS holds a Grant Agreement on the property.

The AllTrails website has a description and map of a hike at Fall Mountain State Forest.