ONE-DAY TRIPS FROM DENVER.
As most of the westbound travelers who pass through Denver stop over a few hours or a few days, it is desirable to call their attention to many side trips that may be made in one day by trolley, railroad train, or automobile.
Most people are attracted by the mountains, and the excursions that are generally of the greatest interest are those made into their narrow canyons or over their snowy summits. Not only are the mountain trips enjoyable on account of the scenery, but they enable the traveler to have the pleasure of tramping over snow banks under the hot rays of a midsummer sun, to see something of the mines of gold and silver and other metals that have made this region famous, and to behold the magnificent exposures of rock along the canyon walls and in the highest peaks and thus to learn some of nature's hidden mysteries regarding the earth upon which he lives.
CONTINENTAL DIVIDE AT CORONA IN ROLLINS PASS.
Corona is reached by the Denver & Salt Lake Railroad, or "Moffat road," as it is generally called. It is the objective point of most travelers who wish to enjoy the pleasure of snowballing on a hot summer day and of experiencing the sensation of standing on the backbone of the continent. On leaving Denver for this trip the traveler sees first the fine irrigated farms of Clear Creek valley (see Pl. III, A) and then the upturned beds of sandstone and shale which carry the coal of the Denver Basin. These rocks, which are called by geologists the Laramie formation, are of Cretaceous age, and their position in the geologic column is shown on page II. No coal beds can be seen from this railroad, but a few miles to the north there are extensive mines.1
At the loop which the railroad makes before it climbs the eastern front of the mountains there is exposed a dark shale (Benton shale or lower part of the Colorado group), which lies near the base of the Upper Cretaceous series. At Plainview the road cuts through a hogback2 formed of the upturned edge of the underlying Dakota sandstone and shows some of the variegated sandstone and shale of the Morrison formation, which lies directly below the Dakota sandstone, or toward the mountains. The succession of rocks in the hogback and the mountain front is shown in figure 2. Beyond the valley formed in the soft rocks of the Morrison formation the red sandstone (Fountain formation) lies upturned against the mountain front in great triangular slabs like the teeth of a gigantic saw. (See Pl. III, B.) The railroad in climbing the mountain front pierces the projecting points of this hard layer by many short tunnels, and the traveler has ample opportunity to study its characteristics as the train turns and twists around the ravines or dives headlong through the rocky tunnels. (See Pl. IV, A). This red sandstone is tilted up against the gneiss (pronounced nice) or granite-like rock that forms the bulk of the Front Range.
When these beds of sandstone were formed they consisted of horizontal layers of sand, which were laid down along the shore of a body of water, just as sand accumulates to-day along the shore of the ocean or of a large lake. The rocks upon which the sand rested were granite and gneiss, from which some of it was derived, and the sand lapped onto the shore irregularly, some beds extending much farther inland than others, the distance inland reached by them at one place or another depending on the form of the surface and the height of the water. Finally, after the entire region had been covered by layers that eventually became sandstone, shale, and limestone, the region on the west was lifted up hundreds or perhaps thousands of feet, and the red sand, which had hardened into sandstone, was bent upward in a great arch that may have extended entirely over the present Front Range. The streams probably cut away the upper part of this arch almost as fast as the land was raised, so that the mountains may never have been much higher than they are to-day. The work of the streams has been continued until all of the upper part of the sandstone arch has been removed, as shown in figure 3, and only the sharp upturn on the flanks, which can be seen so well from the "Moffat road," has been preserved.
The train climbs steadily, affording here and there beautiful views far out over the plains to the east, and finally, when nearly above Eldorado Springs, it turns suddenly to the left and enters a tunnel that leads through the heart of the mountains. Beyond this tunnel the roadbed is in granite,3 and the banding of this rock gives little indication of the real structure of the mountain range. The streams have cut deep canyons, and many interesting views may be seen on the right of the train as it passes from branch to branch of South Boulder Creek, here crossing a canyon on a high trestle and there plunging into the darkness of a tunnel through a spur. Where South Boulder Creek is first seen it lies far below the level of the road, but its bed slopes steeply headward and is finally crossed by the railroad well above the sharp canyon, which represents the latest period of stream cutting in this region. If the trip is made in July the traveler may have the pleasure of seeing in the foothills acres of the beautiful Rocky Mountain columbine (Pl. IV, B), which has been adopted as the floral emblem of Colorado. The plant grows about 3 feet high, and each stalk bears a number of delicate lavender-tinted blossoms which become white as the season advances.
The first large village above the point where the railroad crosses South Boulder Creek is Rollinsville. Here the traveler sees no suggestions of mining, but if he could follow for a distance of 4 miles the road that climbs the hill on the north (right) he would find himself in a district that furnishes the metal for the filaments of most of the incandescent electric bulbs made in this country. This metal is tungsten, and a small percentage of it is contained in the steel from which most of the modern machine tools are made.
A few miles below Tolland the valley changes from a rocky V-shaped ravine to a broad valley having a U-shaped cross section. The meaning of such a change is shown in figure 4. The mountain valley shown in figure 4, A, has been carved only by the stream which occupies it. The walls slope gradually from the ridge on either side to the stream in its bottom, and the form of a section of such a valley, if cut directly across, would be a flat V. If after its excavation by the stream this same valley had been occupied by a glacier the ice would have ground away the projecting spurs on its sides and left it in the form shown in figure 4, B. The cross section of a valley is a nearly infallible indication whether the valley has been carved by running water alone or has been modified by ice. Thus the change from a V shape to a U shape a few miles below Tolland marks the point of farthest extension of the old glacier that had its source near the summit of James Peak and filled this valley with ice to a depth of many hundreds of feet if not a thousand feet. Usually the foot of a glacier of this magnitude is marked by a terminal morainea ridge of loose material carried down by the icebut if such a moraine was ever built in this locality it has been washed away by the stream swollen with the waters of the melting ice.
Although the valley at Tolland and for some distance above that place is broad and the slopes are smooth, it soon terminates abruptly at the foot of the Continental Divide, and no railroad can ascend it much farther and succeed in crossing the range. Consequently the engineers were forced to turn aside from what seems to be an easy pathway up the valley and construct the road to the summit in a roundabout way by scaling the valley walls. The train makes this climb with many turns and twists, and the traveler is generally deeply impressed with the care and precision with which the engineers fitted the roadbed to the mountain slopes. To the railroad engineer no slopes are too Steep for railroad construction, provided he can find ground sufficiently level to enable the road to curve around and double back upon itself, thus zigzagging its way up the mountain slope. The train climbs steadily upward, and one by one the ridges that from below seemed to be of great height are surmounted and they are found to be only low spurs of the still higher mountains above.
As the train nears the summit and encircles the little pond called Yankee Doodle Lake, the traveler may see some of the effects, other than the rounding of valleys, that the old glaciers have produced on the mountain scenery. In the canyons below, where the ice moved down in a great stream from the heights above, its effect was to smooth and round the slopes and to do away with much of the ruggedness that must have marked these canyons before they were occupied by the ice. Near the summit the ice scooped out in the side of the mountain great amphitheaters, called cirques, making the tops much more rugged than they were before. The circular depression that holds Yankee Doodle Lake is such a cirque, and all the vast rock slopes above the lake have been steepened by undercutting by the ice. Other cirques (such as those shown in Pl. V) may be seen in the mountains; indeed, the entire front above this place, up which the railroad finds, its way to the summit, consists of the walls of cirques that have united. The steepness of this slope is due almost entirely to the action of ice. In places the road is constructed along the upper edge of one of these great cirque walls, and the traveler may look down on the right nearly 1,000 feet into the cirque below. Although the cliff has an appreciable slope, it appears to be vertical especially when viewed from the moving train.
At last the traveler reaches the summit, at Corona, 11,680 feet above the level of the sea, but the great snowsheds through which the train passes have prevented him from getting a fair view of the mountain summit. As soon as the train stops at Corona he may pass from the confinement of the snowshed and enjoy to the utmost the boundless space of the mountain top. On the crest in any direction there are peaks higher than Corona, the most prominent being James Peak (13,260 feet) on the south and Longs Peak (14,255 feet) on the north, but they can be seen from only a few points. On the west the traveler can look down on the billowy surface of Middle Park, one of the surface basins in the midst of the mountains; and on the east he can look over the wide expanse of spur and ravine up which the train has so laboriously climbed.
The railroad beyond Corona descends the fairly smooth western slope of the Front Range by many loops and turns until it reaches the floor of Middle Park. It crosses this immense basin in the heart of the mountains, cuts through the Gore or Park Range beyond in a deep, rugged canyon, and then continues westward across the great plateau country of north-western Colorado. The plateau contains one of the great coal fields of the State, which has only recently been developed. The coal is better than that of the Denver Basin, and much of it finds a ready market in the towns on the plains between Denver and Omaha.
Last Updated: 16-Feb-2007