Photographs by Lee Friedlander taken during the Prayer Pilgramage for Freedom in 1957 are featured in the Yale University Art Gallery exhibit "Let Us March On," which is on view through July 9. All of the images are gelatin silver prints and are gifts to the Yale University Art Gallery from Maria and Lee Friedlander, HON. 2004. © Lee Friedlander, courtesy of Fraenkel Gallery, San Francisco. Photos courtesy of Eakins Press Foundation.