Big Basin Prairie Preserve is located in southwest Kansas, west of Ashland in Clark County. Big Basin is a natural, 100 foot deep circular, crater-like depression about a mile in diameter. Big Basin is listed on the National Register of Natural Landmarks. 

The Preserve includes Little Basin which surrounds St. Jacob’s Well, a natural sinkhole with a permanent, spring-fed pool of water. Big Basin and St. Jacob’s Well were prominent landmarks used by Native Americans and early settlers. Archeological studies indicate that St. Jacob’s Well has attracted travelers for many centuries, beginning with prehistoric peoples, then Native Americans, followed by non-native peoples and continuing through today. Nearly 300 Northern Cheyenne camped in the area in the fall of 1878 during the Northern Cheyenne Exodus as they traveled from Oklahoma to areas in Nebraska and Montana. The well was also used by drovers moving cattle from Texas to the Kansas railroads in the late 1800s.

Big Basin Prairie Preserve is home to herds of American bison allowed to graze as part of the natural process of maintaining the prairie ecosystem. Vehicles are allowed only on specified minimally-managed trails. Hiking is permitted, but visitors should not approach or harass the bison as they are wild animals and can be unpredictable. It is not possible to outrun a bison.