A. View west across Jackson Lake. Major peaks, canyons, and outcrops of sedimentary rocks are indicated by “s.”
[High-resolution View]

B. View northeast; a study in contrast with the panorama above.
[High-resolution View]

Three steepsided hills called buttes rise out of the flat floor of Jackson Hole. They are tilted and faulted masses of hard, layered rock that have been shaped by southward-moving glaciers. Six miles north of the boundary turnout is Blacktail Butte, on the flanks of which are west-dipping white beds. Southwest of the turnout is East Gros Ventre Butte, composed largely of layered rocks that are exposed along the road from Jackson almost to the turnout. These are capped by very young lava that forms the brown cliff overlooking the highway at the north end of the butte. To the southwest is West Gros Ventre Butte, composed of similar rocks.

View west.—

The motorist traveling west along U. S. 26-287 is treated to two magnificent views of the Teton Range. The first is 8 miles and the second 13 miles west of Togwotee Pass. At these vantage points, between 20 and 30 miles from the mountains, the great peaks seem half suspended between earth and sky—too close, almost, to believe, but too distant to comprehend.

Only from closer range can the motorist begin to appreciate the size and steepness of the mountains and to discern the details of their architecture. The many roads on the floor of Jackson Hole furnish ever-changing vistas, and signs provided by the National Park Service at numerous turnouts and scenic overlooks help the visitor to identify quickly the major peaks and canyons and the principal features of the valley floor. Of all these roadside vantage points, the top of Signal Mountain, an isolated hill rising nearly 1,000 feet out of the east margin of Jackson Lake, probably offers the best overall perspective ([fig. 3]). To the west, across the shimmering blue waters of Jackson Lake, the whole long parade of rugged peaks stretches from the north horizon to the south, many of the higher ones wearing the tattered remnants of winter snow. From here, only 8 miles away, the towering pinnacles, saw-toothed ridges, and deep U-shaped canyons are clearly visible.

Unlike most other great mountain ranges, the Tetons rise steeply from the flat valley floor in a straight unbroken line. The high central peaks tower more than a mile above the valley, but northward and southward the peaks diminish in height and lose their jagged character, gradually giving way to lower ridges and rounded hills. Some of the details of the mountain rock can be seen—gnarled gray rocks of the high peaks threaded by a fine white lacework of dikes, the dark band that cleaves through Mount Moran from base to summit, and the light brown and gray layers on the northern and southern parts of the range.

At first glance the floor of Jackson Hole south of Signal Mountain seems flat, smooth, and featureless, except for the Snake River that cuts diagonally across it. Nevertheless, even the flats show a variety of land forms. The broad sage-covered areas, low isolated hills, and hummocky tree-studded ridges that form the foreground are all parts of the Teton landscape, and give us clues to the natural processes that shaped it. A critical look to the south discloses more strange things. We take for granted the fact that the sides of normal valleys slope inward toward a central major stream. South of Signal Mountain, however, the visitor can see that the Snake River Valley does not fit this description. The broad flat west of the river should slope east but it does not. Instead, it has been tilted westward by downward movement along the Teton fault at the base of the mountains.