March 26, 2018 Entrance to Blue Hole, Castalia, Ohio (Date Unknown) R.G. Tremper Sales Co. | Curt Teich | Linen | c. 1930-1940s
January 16, 2018 Crystal Cave, Put-In-Bay, Ohio (Date Unknown) E.B. Ackley | Curt Teich | Linen | c. 1930-1945s
January 16, 2018 Entrance to Snyder Park, Springfield, Ohio (1907) American News Company | Undivided Back | c. 1907
January 15, 2018 Blue Hole Entrance, Castalia, Ohio (1940) E.B. Ackley | Curt Teich | Linen | c. 1940
January 15, 2018 The Gateway to the Blue Hole, Castalia, Ohio (1936) Standard Publications | Fort Wayne Printing Co. | Linen | c.1936
