Thru hiking is a term used in referring to hikers who complete long-distance trails from end to end in a single trip. The Pacific Crest Trail, Appalachian Trail, and Continental Divide Trail were the first three long-distance trails in the U.S.. Successfully thru-hiking all of these three trails is known as the Triple Crown of Hiking. Thru-hiking is a long commitment, usually taking between four and six months, that requires thorough preparation and dedication. The Pacific Crest Trail Association estimates that it takes most hikers between six and eight months to plan their trip.