Timpanogos Cave National Monument is a United States National Monument protecting the Timpanogos Cave Historic District and a cave system on Mount Timpanogos in American Fork Canyon in the Wasatch Range, near Highland, Utah, in the United States. The site is managed by the National Park Service. The trail to the cave is steep, gaining close to , but paved and fairly wide, making the caves accessible to most. The three caves of the system, one of which is specifically called Timpanogos Cave, are only viewable on guided tours when the monument is open, usually from May through September depending on snow conditions and funding. There is the standard tour going through the cave system, and an Introduction to Caving tour which teaches Leave No Trace caving and goes further into Hansen Cave. Three caves The three caves of the Monument that are tourable are: Hansen Cave, Middle Cave, and Timpanogos Cave. The three caves are connected by manmade tunnels blasted in the 1930s by the Works Progress Administration . The average temperature in the caves is 46 degrees Fahrenheit. Many colorful cave features or speleothems can be seen. Among the most interesting are the helictites, which are hollowed, twisted, spiraling straws of deposited calcite or aragonite. They are formed when water travels through the tube and then evaporates, leaving a trace mineral deposit at the end. Other speleothems found in the cave include: cave bacon, cave columns, flowstone, cave popcorn, cave drapery, stalactites and stalagmites. Discovery of the caves Martin Hansen discovered what became known as Hansen Cave in October 1887, reportedly while cutting timber he tracked cougar footprints high up the side of American Fork Canyon. Many of the features and formations in this chamber were damaged or removed by the Duke Onyx Company and the general public before the cave was made a national monument. In 1913, a second cave was discovered nearby. While in the area to explore Hansen Cave with their families, James W. Gough and Frank Johnson were climbing an adjacent slope when they discovered the entrance to what is now known as Timpanogos Cave. Several others later entered the cave and viewed many of the formations inside, including the Great Heart of Timpanogos. However, before long knowledge of the cave and its entrance was lost. Some sources indicate that the entrance was lost due to a landslide in the area, while others say