(Francisco Kjolseth | Tribune file photo) A measuring stick far below keeps track of the depth of the Hansen Cave Lake that make up the far end of the introduction to caving tour at Mt. Timpanogos and where Martin Hansen conducted tours in the late 1800s. The side tour gives those 14 and older a chance to experience caving away from the developed trail and cave lights. With a helmet lamp and a ranger to guide you visitors experience tight spots that force you to crawl and scramble.