Types of Trails
Rail trails

In the early 1900s there were more than 300,000 miles of railroads carrying passengers and goods to all corners of the United States. With the consolidation of railroad companies, the advent of the automobile, and the rise of the interstate system, this network has now dwindled to less than 140,000 miles. Since as early as 1939, the corridors left behind by the railroads have been converted into places for people to walk and bicycle. The Rails to Trails Conservancy estimates that in 2005, there were more than 1,200 trails extending more than 13,150 miles throughout the United States.
While rail trails cannot replace streets and sidewalks, the conversion of the extensive network of disused or abandoned railroads in communities throughout the United States nicely supplements the traditional roadway system of on-road bicycle facilities.
Many of the best communities for bicycling and walking in the United States feature rail trails as the backbone of their facility networks. The City of Seattle has the Burke Gilman Trail; in Washington D.C., the Capital Crescent and W&OD; trails link suburban Maryland and Virginia with the nation's capital; Boston's Minuteman Trail, Tampa's Pinellas Trail, and the Iron Horse Trail (in the San Francisco Bay area) each carry hundreds of thousands of users every year.
Canal towpaths trails
Before railroads, a network of canals moved people and goods throughout the northeast and mid-west. Every canal was built with a towpath to enable horses to draw the canal boats and barges—and these paths are now ideal for runners, joggers, equestrians, and bicyclists. A 1996 study, by the National Park Service and Rails to Trails Conservancy, identified more than 1,000 miles of trail alongside 35 historic canals, with hundreds of miles of additional projects underway.
A great example is the C&O; Canal Trail, which extends more than 180 miles west from the District of Columbia, following the towpath of the canal through Maryland, West Virginia, and Pennsylvania. The 320-mile Erie Canal, connecting the Hudson River to Lake Erie in upstate New York, has a trail along its entire length, both on-road and on the canal towpath. The 68-mile Delaware and Raritan Canal towpath has been converted into one of New Jersey's premier trails taking riders or walkers from Frenchtown to New Brunswick, via Trenton.
Rails with trails
Even though many railroad corridors are more than 100 feet wide and have a single line in operation, placing trails alongside active rail lines is very difficult and is usually not allowed by railroad companies. Some of the issues that need to be addressed include trespassing, debris falling off moving trains, crossing active lines, and maintenance of the trail corridor. Additionally, relatively inactive lines can sometimes become very active, making a trail inappropriate or requiring a trail to be removed to accommodate an additional line.
The existence of about 60 rails-with-trails encompassing more than 230 miles in 20 states (in 2001) indicates that these concerns can be overcome with careful planning, design, and management. Among the strategies currently being pursued are:
- Locating the trail as far away from the active rail line as possible
- Separating the trail from the rail line with fencing and vegetation
- Posting clear warnings and education materials to prevent trespassing
- Clearly marking the trail to heighten the distinctions between trails and railroad maintenance corridors
- Grade separating trail and rail line intersections
Another strategy is to purchase part of the corridor adjacent to the active rail line, thus removing the railroad company from having to be concerned about a trail on their property.
The Federal Railroad Administration (FRA) is in the process of developing a best practices report to address these issues and assist in the planning, designing and operation of new "Rails-with-Trails" (RWT).