Potomac Area Council American Youth Hostels (PAC-AYH) is an organization that promotes outdoor recreational activities and runs three youth hostels in Washington, Harper's Ferry, West Virginia, and Baltimore. It is affiliated with Hostelling International and Hostelling International USA (formerly American Youth Hostels (AYH)).

Justin Cline founded the Potomac Area Council in 1943 as an offshoot of the international hostelling movement. The organization's mission was to "develop healthy, self-reliant, well-informed, community-minded and world-minded citizens and to further good will among people of all lands." To accomplish this, the organization promoted inexpensive outdoor and social activities for people of all ages, such as dances, bicycling, and hiking. As a secondary function, it established low-cost accommodations for travelers engaged in these activities.

In its early years, the organization focused on providing recreational opportunities for the multitudes that swarmed to Washington during World War II. After the war ended, many of its members stayed in Washington and continued to organize recreational activities and establish hostels. In the early 1950s, it became active in promoting trails, including working with Supreme Court Justice William O. Douglas in the preservation of the Chesapeake and Ohio (C&O) Canal (see C&O Canal Association records, MS2027). PAC then established a now-defunct chain of hostels for hikers along the canal. It also ran a bicycle concession at Hains Point in East Potomac Park. During this time, the group was relatively small and centered on recreational activities for its members.

In the late 1960s, however, it began to reach out more to the surrounding community. Although PAC began bicycling programs for inner city youth in the early 1950s, it expanded them in the late 1960s and early 1970s. It would continue to promote bicycling through the 1980s, and continues to provide programs for inner city youth today.

An offshoot organization, the Boot & Sprocket Club, formed from some of the original hostellers after marriage and "settling down." The organization continues to hold reunions.

Today, running hostels is the main function of PAC. The organization has managed several hostels in the Washington area through its history. PAC's main hostel, as well as its headquarters, is currently located at 11th and K Streets, NW, in Washington.

PAC has published several newsletters and brochures, as well as hiking and bicycling guides.

Don Messersmith, a professor of Entomology and Ornithology at the University of Maryland, has been involved with PAC since 1950 and once served as its executive director and president of the board. As the donor, he is the most prominently featured individual in the collection.