Browse Items (1 total) Street Address is exactly "Mt. Gretna (Pa.)" Browse All Search Items Browse Map Browse by Headings Sort by: TitleCreatorDateDate Added Items open in a separate tab. Close the tab to return to this list. Company “M” 111th, Mt. Gretna Address: Mt. Gretna (Pa.) Date: 1927 This was part of the Pennsylvania National Guard unit based in the Media Armory, at camp in Mt. Gretna, Pennsylvania. Paul Clark is second from left; the rest are unidentified.