13-8 Postcards from Mammoth Cave: Geoheritage Documentation of Evolving Landscapes and Public Perceptions

Session: Building Connections Between Educators and Geoscientists to Foster the Future Workforce

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Abstract:

Mammoth Cave is an internationally recognized geoheritage site. To evaluate how public-facing portrayals of the cave system’s geoheritage have shifted through time—and whether those shifts reflect changing cave conditions and societal norms—we conducted a pilot investigation of twentieth-century Mammoth Cave souvenir postcards archived at the National Cave Museum (Park City, Kentucky). We reviewed postcard imagery and captions alongside temporal and contextual cues (postmarks, card materials, printed dates, and publisher/series information where available) to identify recurring themes in what was framed as “iconic” and worth seeing. The earliest postcard in our sample (dated 1 April 1901) featured the formation “Olive’s Bower.” Other early 1900s postcards commonly depicted the Mammoth Cave boat tour, “Elizabeth’s Parlor” with gypsum-rich speleothems, the “Martha Washington’s statue” lighting illusion, and the fallen “Giant’s Coffin” breakdown block. Collectively, these cards document geoheritage as dynamic rather than static. It is no longer possible to replicate the original boat-tour experience because the 1908 dam on the Green River raised water levels and changed navigability, thereby altering what visitors could do and what operators could interpret. Importantly, postcard-era changes were not the endpoint—Green River stage management has continued to evolve, including the failure and subsequent removal of Lock and Dam No. 6 in 2016, which affected water levels and currents and provides a useful “continued change through time” context for interpreting historic tour imagery. Postcards also record changing cultural values and interpretive ethics. Early twentieth-century cards frequently showcased “The Lady of the Cave,” an Indigenous woman’s mummified remains displayed near the new entrance that opened in the 1920s, reflecting contemporary fascination with mummies and stereotyped portrayals of Native Americans. In parallel, postcards show African American guides as central figures in the visitor experience; several prominent guides were featured in photographic postcards which they themselves sold to tourists, followed by a documented rupture when the National Park Service assumed operations in 1941 and African American guides were dismissed. These twentieth-century postcards therefore function as both geoheritage data and a cultural archive, preserving evidence of changing environments, visitor routes, labor histories, and interpretive practices before and after establishment of the national park. This pilot provides a replicable framework for expanded, quantitative content analysis across larger postcard collections.

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