Bikecentennial '76 was an event consisting of a series of bicycle tours on the TransAmerica Bicycle Trail across the United States in the summer of 1976 in commemoration of the bicentennial of America's Declaration of Independence. The route crossed ten states, 22 national forests, two national parks, and 112 counties between Astoria, Oregon, and Yorktown, Virginia, a distance of about . The route was chosen to take cyclists through small towns on mostly rural, low-traffic roads. About 4,100 riders participated in the event, representing all 50 states and many foreign countries. Several route options were available to the participants, ranging from an 82-day, 4,250-mile cross-country trip to a more modest 12-day trip through the Rocky Mountains. Roughly 1,750 cyclists were signed up to ride the entire length of the trail. Most of the participants rode in prearranged groups of 10 to 12 with a group leader, while about a quarter rode solo. The riders were essentially self-contained; they carried camping gear, food, and other necessities in panniers on their bicycles. Bikecentennial had been a 501(c)(3) nonprofit since 1974, and after the 1976 event the organization lived on to serve the needs of traveling cyclists, developing more routes and making maps. Bikecentennial changed its name in 1993 to Adventure Cycling Association. Origin A 1976 bicycle tour across the United States was conceived by Greg Siple in 1973 while he, his wife June, and Dan and Lys Burden were riding an 18,000-mile bicycle tour, called Hemistour, from Anchorage, Alaska, to Tierra del Fuego, Argentina, to promote bicycling and hosteling. June Siple coined the name Bikecentennial a few months later as Hemistour progressed through Mexico. Siple had founded an annual bicycle tour called the Tour of the Scioto River Valley (TOSRV) in Ohio with his father in 1962. During a break from Hemistour, Dan Burden became severely ill and had to drop out. He and his wife, Lys, focused on building the Bikecentennial event while the Siples continued their tour of the Western Hemisphere. Route Bikecentennial's route, called the TransAmerica Bicycle Trail, was developed by Lys Burden with the help of Bikecentennial staff and volunteers. The route was chosen to satisfy several requirements, such as a road surface suitable for bicycles, minimal traffic, varied terrain, historic and interesting landmarks, and access to basic services like campgrounds and grocery stores. The Bikecentennial TransAmerica Trail should not be confused with the similarly named Trans America