Martin "Marty" Perry Knowlton (July 30, 1920 – March 12, 2009) was the American co-founder of Elderhostel, a non-profit organization established in 1975 that allows senior citizens to travel and take educational programs in the United States and around the world.
Knowlton was born in Dallas, Texas on July 30, 1920. In 1940, he left college to join the Free French Forces, where he served in the Middle East as an ambulance driver and was awarded the Croix de Guerre. He joined the United States Army in 1942 and served as a medic in the Pacific Theater and was awarded the Silver Star.
Following the completion of his military service, Knowlton attended Birmingham-Southern College, where he was awarded a degree in history in 1946. He earned a master's degree in 1949 at the University of North Carolina at Chapel Hill, where he majored in political science, and later served on the school's faculty. He worked at a number of firms in Maine after graduation and returned to Yale University and Boston University for further graduate education. He was a teacher at high schools, including at Brookline High School, where he coached the school's chess team to the 1970 national championship.
Knowlton ran the American Youth Hostels program at the University of New Hampshire, where he envisioned a program that would combine the features of youth hostels with the adult folk school programs he had seen while backpacking through Europe. David Bianco, who supervised the dormitory and dining programs at UNH and had hired Knowlton to run the hostel based on their connections at Boston University, brainstormed about the concept. "Elder hostel" came out as a name, after Bianco saw self-described hippie Knowlton with his white beard sitting under a sign saying "youth hostel".