In 1987 the National Park Service and Golden Gate National Parks Conservancy launched the Alcatraz Cellhouse Tour as part of the interpretive program educating visitors about the island and its history. Using an existing format made possible several years previously by Sony Walkman™ technology, the designers framed this individual, and innovative, audio tour as a means for visitors to experience the cellhouse through the voices of people incarcerated there, or living and working there, during the years when it served as an active federal prison. Such a design called for different decisions about content, scripting and moving people through space than had been required for ranger-led tours or the lecture-type audio tours prevalent at the time. The original tour has been updated continuously since its launch, and experienced by millions of visitors in multiple languages. The author of this case experienced the tour in 1988 and interviewed key designers in 2014.