Mammoth Cave National Park in Kentucky and Saguaro National Park in Arizona are the two most recent National Park Service (NPS) properties to allow mountain biking on both existing and future trails.
The regulation at Mammoth Cave opened two existing and two future trails to bicycle use on Oct. 12, 2012. Mountain bikers now have access to the Mammoth Cave Railroad Bike and Hike Trail and the White Oak Trail, and will have access to the planned Connector Trail near Maple Springs and Big Hollow Trail north of the Green River.
A press release from Mammoth Cave stated: "The regulation designates four bicycle routes within the park to address the interest and demand of the visiting public for bicycling opportunities without compromising the National Park Service's mandate 'to conserve the scenery and the natural and historic objects, and the wildlife' in the park."
The regulation implements portions of the park's Comprehensive Trail Management Plan and satisfies NPS general regulations that require a special regulation be promulgated to allow off-road bicycle use on routes outside of developed areas.
On Dec. 1, 2012, the three-mile Hope Camp Trail in Saguaro National Park (AZ) will be converted to a multi-use trail. The trail — once a dirt road that allowed bikes prior to Saguaro's National Park designation — connects Tucson, AZ, to the Arizona Trail.
Source: http://www.imba.com/news/two-national-p ... ain-biking