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Leaving the Grand Geyser Complex to the north, you come across the small Topsoil Spring left of the boardwalk. It shows boiling and small eruptions only on rare occasions.
At larger distance to the west the quiet, deep blue Calida Pool can be spotted. The field between the boardwalk and Calida Pool and also north of Calida Pool is occupied by a group of small springs, informally called "Bush Group". Some of them are capable of eruptions of several feet height, but that is rarely seen.
As the trail progresses, it passes three quite similar round hot springs, which usually exhibit thick orange-brown bacterial mats on their walls. All have a history as a geyser and all are dormant for decades now. The first (southernmost) one is Economic Geyser, followed by East Economic Geyser and by Wave Spring.
Next stops on the trail are Beauty Pool and Chromatic Pool. Once they belonged to the most outstanding pools of the Upper Basin, but in the last years both cooled down and lost much of their bright coloration. Anyway, Beauty Pool and Chromatic Pool remain the classic examples for an exchange of function between thermal features in a sense that the primary supply with hot water shifts from one to the other and back again at intervals between days and a year. On location the particular status is easy to recognize because the privileged pool overflows and shows a bright blue center, encircled by a yellow rim of bacterial mats, while the other one appears to be dull and stagnant.
Two further features of the Grand Group, Limekiln Springs and Witches Cauldron, are located on the bank of Firehole River. They can be spotted from the old road leading from Old Faithful Geyser to Morning Glory Pool. Viewpoints are to be found approximately 1 km (0.6 miles) northwest of Old Faithful along the trail between Orange Spring Group and Round Spring Group. The Limekiln Springs, a collection of small perpetual spouters, are to be seen from there quite easily.
Witches Cauldron is a superheated boiling and strongly steaming pool, sitting beyond Limekiln Springs almost at water level of the river. For a slightly better view with binoculars or a long telephoto lens you may look for gaps between the trees flanking the road.
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