A popular trail with a good portion on boardwalks. May be crowded.
The Mammoth Terraces Trail snakes more than 300 feet up the Mammoth Terraces to a wonderful overlook of the Main Terrace on Upper Terrace Drive. Along the way the trail passes many of the most beautiful and historic hot spring terraces in the park. Start the trail at any of 4 parking areas at the base of the terraces. From north to south, the areas are near: (1) the restroom; (2) Liberty Cap; (3) beneath Minerva Spring; and (4) beneath Jupiter Terrace.
From the restroom parking the trail travels south toward Liberty Cap, a 37-foot tall extent hot spring cone. Just past Liberty Cap the short Palette Springs Spur
trail affords nice views of Palette Springs and the Devil’s Thumb.
The trail continues past the 2nd parking area along the road to the 3rd parking area, then turns right and begins climbing into the terraces. The terrace travertine formations are made of calcium carbonate. Beneath lies thick layers of sedimentary limestone, deposited millions of years ago by vast seas. The hot springs water contains dissolved carbon dioxide gases which form a weak carbonic acid. This hot, acidic solution dissolves great quantities of limestone as it works up through rock layers to the surface. Once exposed to the open air, some of the carbon dioxide escapes from solution. As this happens, limestone can no longer remain in solution and it is deposited in these beautiful travertine formations. These deposits can grow very fast - as much three feet a year!
As springs shift and formations grow, the boardwalks are often rerouted to protect the features. Look carefully, you can see the scars where boardwalks used to travel. Soon the trail passes a small connector trail down to the 4th parking area and then bends several times to the right. Above you on the left is Jupiter Terrace. In the 1980s, it flowed so heavily that it overtook boardwalks several times. It has been dry since 1992, but when active, its color and intricate terraces make Jupiter special. Past Jupiter, the Mammoth Terraces Trail Connector (on left) provides a more direct route to the top of the Main Terrace.
Our trail continues beneath now-dormant Minerva Spring (a short spur takes you closer) then loops back to the left and climbs above it. The last push to the top of the Main Terrace is a bit steep. But the views from the top are nice. The final leg of the trail continues along the Upper Terrace Drive, past a spur trail overlooking Canary Spring, and ends at a parking area on the main road.
Thanks to guidebook author, Tom Carter, for sharing this trail description. To learn more about visiting Yellowstone, check out his book, Day Hiking Yellowstone