On Wednesday, Sept. 2, Historic Rock Fords America250 Lecture Series will present Walls That Witnessed a Revolution: Lancaster County Before 1776, in which Danielle Keperling explores the pre-1776 buildings throughout Lancaster County, Pa. This presentation will begin at 6 p.m. in the Langmuir Education Room located on the first floor of the Rock Ford Barn. Admission is for the lecture only and does not include the Snyder Gallery or Hand Mansion. Danielle Keperling serves as the executive director of the Historic Preservation Trust of Lancaster County, where she advances preservation advocacy, education, and stewardship across the county. She also serves on the Lancaster City Historical Commission, helping oversee the Heritage Conservation District. General admission tickets are $10 and may be purchased at www.HistoricRockFord.org/special-events. Historic Rock Ford, located at 881 Rock Ford Road, Lancaster, Pa., is comprised of the General Edward Hand Mansion and the John J. Snyder, Jr. Gallery. It is owned and operated by the Rock Ford Foundation, a private, not-for-profit corporation.