Hierve el Agua mountainside. The water has a temperature of . As the water runs down the rock face, it forms large stalactites similar to those found in caves. The flow of water from the spring varies significantly between the dry and rainy seasons. 95% of the surface rock formations are of calcium carbonate; however, lower layers of both rock and water currents are little known as they are sealed by the above layers. The calcium carbonate gives the formations a white or near white appearance, but other minerals that can be present in the water, such as silver, barium and iron can
Cave of the Winds (Colorado) Cave Coral, or Cave Flowers; also commonly considered to be Beaded Helectites which appear to defy the laws of gravity by growing in strange directions and not being forced down by gravity like many cave formations. Silent Splendor is sealed from public view by an Environmental Gate, a large tube made of PVC that seals in moisture to allow the area of the cave to continue forming. Other lesser known attractions include a "bottomless pit," often the scene of practical jokes by the guides, and a one of a kind region referred to as "the rat." In the late 1980s