[Fig. 43(4)] The rocky spires of the Chimney Tops rise 50 feet above the summit of Sugarland Mountain. Climbing well above the tops of the surrounding trees, they offer a rare assertion in the forest-blanketed Smokies of the power and might of stone. To settlers, the twin pinnacles must have been a reassuring sight, a landmark as orientating as the top of a neighbor's chimney spied above the tree line. The resemblance of the rocky spires to a chimney holds true close up as well: each pinnacle has a shaft, or a chimney hole, winnowed into its left side.
The Chimneys are an outcropping of the Anakeesta Formation, the Precambrian rock layer that forms much of the crest of the Smokies. Composed of metamorphic slates, schists, and phyllites, Anakeesta is the dark gray color of clay and, in exposures like the Chimneys, is burnished with a rust color that results from oxidation of the iron sulfide in the rock. Pyrite, commonly called "fool's gold," often adds flecks of metallic tint to Anakeesta as well, another indication of the high sulfide content that has earned the formation the nickname "acid rock." The slate layers of Anakeesta break apart relatively easily, and it is this characteristic that has created so many of the steep-sided ridges of the Smokies as well as such rakish outcroppings as the Chimneys and Charlies Bunion (see Charlies Bunion).
Typical of the Smokies, the Anakeesta of the Chimney Tops lies atop a layer of rocks known as the Thunderhead Formation. Exposures of Thunderhead can be seen from the bridges that cross over the West Prong and Road Prong of the Little Pigeon River near the bottom of the trail to the Chimneys. A gritty, light-gray sandstone, Thunderhead is extremely resistant to weathering, and in the creek beds, its uplifted strata makes the water crash around it.
The 2-mile uphill hike to the Chimneys is steep and strewn with small boulders, but it's well worth the panoramic view from the top. It's also not without its rewards along the way. In addition to great tangles of rhododendron, the creek area hosts shadbush (Amelanchier laevis) and trilliums in spring, and in summer, bee-balm (Monarda didyma), jewelweed (Impatiens capensis), and joe-pye weed (Eupatorium maculatum). As it climbs, the trail passes through two beech gaps resplendent in spring with such wildflowers as fringed phacelia (Phacelia fimbriata), Dutchman's breeches (Dicentra cucularia), spring beauty (Claytonia caroliniana), trout lily (Erythronium americanum), and squirrel corn. Coves of yellow buckeye and yellow birch (Betula lutea)—both known for autumn foliage in their signature color—gradually give way to hemlock, red spruce, mountain laurel, and more rhododendron near the trail's end.
Late-spring and summer birds in this area of the park include ruffed grouse (Bonasa umbellus), pileated and downy woodpeckers (Bonasa umbellus and Dendrocopos pubsecens), white-breasted nuthatch (Sitta carolinensis), wood thrush (Hylocichla mustelina), solitary and red-eyed vireos (Vireo solitarius and Vireo flavoviridis), black-throated green warbler (Dendroica virens), black-and-white warbler (Mniotilta varia), black-throated blue warbler (Dendroica caerulescens), and scarlet tanager (Piranga olivacea).
(Note: Extreme caution should be used when climbing on the rock exposures, especially near the chimney holes and in inclement weather. Injuries have occurred when people attempted to climb beyond the trail to the second, northerly pinnacle.)