Martel’s own copy of the Hovey 1912 guidebook to Mammoth Cave has his routes marked faintly in pencil on the printed cave plans. These plans are reproduced here, with his routes indicated on them. He generally followed the four standard tourist routes which now included Kaemper’s 1908 discoveries to Violet City, but instead of visiting the Maelstrom he went to Hovey’s Cathedral and Gerta’s Grotto.
Shaw, Trevor R..
Martel's routes in Mammoth Cave, Kentucky, 1912.
International Journal of Speleology,
Available at: https://digitalcommons.usf.edu/ijs/vol32/iss1/3