This is the main terrace and I never get tired of looking at it. Mostly because it's ever-changing and never looks quite the same whenever I visit.

Travertine terraces are formed from limestone. Thermal water rises up through the limestone, and carrying high amounts of dissolved limestone (calcium carbonate). At the surface, carbon dioxide is released and calcium carbonate is deposited, forming travertine, the chalky white mineral forming the rock of travertine terraces. The formations resemble a cave turned inside out. Colorful stripes are formed by thermophiles, which are actually heat-loving organisms.

Way back, an early visitor to the Mammoth Hot Springs terraces described it this way, "No human architect ever designed such intricate fountains as these. The water trickles over the edges from one to another, blending them together with the effect of a frozen waterfall." I can't think of a better way to describe it. =]:)