The Historical Society of the Cocalico Valley (HSCV) will offer a program, "The Mysterious Petroglyphs of Safe Harbor," on Wednesday, April 23, at 7 p.m. at Holy Trinity Lutheran Church, 167 E. Main St., Ephrata.

Adam Zurn, historian, educator, adventurer, and founder of Uncharted Lancaster, will recount his expeditions down the lower Susquehanna River to explore the mysterious 1,000-year-old Native American petroglyphs hidden in the ancient river rocks at Safe Harbor.

The program is free and open to the public. The parking lot and entrance are accessible via the alley behind the church. For more information, visit http://www.cocalicovalleyhs.org or call 717-733-1616.