American Hiking Society
Dedicated to serving hikers and protecting hiking trails.

American Trails
A national, nonprofit organization working to enhance and protect America's network of interconnected trails. Supportive of local, regional, and long-distance trails and greenways, whether in backcountry, rural or urban areas. Their stated goal is to support America's trails by finding common ground and promoting cooperation among all trail interests.

RailroadData.com
Railroad links directory to 5,237 railroad websites and a search engine. Categories include rail trails.

Rails-to-Trails Act
(common name for the National Trail System Act)
This link takes you to the full text at 16 USC, §1247(d).

Rails-to-Trails Conservancy
The purpose of Rails-to-Trails Conservancy (RTC) is to enrich America's communities and countryside by creating a nationwide network of public trails from former rail lines and connecting corridors. A nonprofit organization with more than 100,000 members and supporters, the RTC was founded in 1986.  See especially Rail Trail History.

TrailLink
A searchable database for detailed information on surface types, access points, locations, distances, services, reviews, photographs and local links for America's 1,177 rail-trails. TrailLink is a service provided by Rails-to-Trails Conservancy.  Another service provided by RTC is the Trails and Greenways Clearinghouse.

Trailnet
A not-for-profit organization dedicated to creating and conserving multi-use recreational trails and greenways.

Trails From Rails
Multi-state listing of many of the best bicycle trails developed from abandoned rail lines.