The Geology and Petrography of Crater Lake National Park, 1902
By Joseph Silas Diller
Routes to Crater Lake
Crater Lake is deeply set in the summit of the Cascade Range, about 65 miles north of the California line. It can be reached only by private conveyance over about 80 miles of mountain roads from Ashland or Medford, on the Southern Pacific Railroad, in the Rogue River Valley of southern Oregon (see fig. 1, p. 18), or from Ager, on the same railroad, in northern California, by way of Klamath Hot Springs and Klamath Falls.
Rogue River Valley marks the line between the Siskiyou Mountains of the Klamath group on the west and the Cascade Range on the east. The journey from the railroad to Crater Lake affords one a good opportunity to observe some of the most important features of this great pile of lavas. The Cascade Range in southern Oregon is a broad irregular platform, terminating rather abruptly in places, especially at the western border, where the underlying Cretaceous and Tertiary sediments come to the surface. It is surmounted by volcanic cones and streams of lava, which are generally smooth, but sometimes rough and rugged. The cones vary greatly in size and are distributed without regularity, a feature which is well illustrated in Pl. II. The photograph was taken across the western edge of Crater Lake. The sharp peak on the right is Union Peak and in the distance is Mount Pitt. Each conical hill has been an active volcano. The fragments blown out by violent eruption have fallen about the orifice from which they issued and built up cinder cones. From their bases have spread streams of lava (coulees), raising the general level of the country between the cones. At some vents many eruptions, both explosive and effusive, have built up large cones, like Pitt, Shasta, and Hood. Their internal structure is revealed by the walls of the canyons carved in their slopes, and they are found to be composed of overlapping layers of lava and volcanic conglomerate. This type of structure is well illustrated in the base of Mount Mazama.
The Dead Indian route from Ashland, Oreg.—The journey from Ashland by the Dead Indian road crosses the range where the average altitude is less than 5,000 feet, and affords a fair view of the low part of the range traversed by the Klamath River. A much better general view of the larger features of the range, and especially of the Crater Lake region, may be obtained front Mount Pitt (elevation 9,760 feet), which lies within a two days’ trip from this road at Lake of the Woods. The road skirts Pelican Bay of Klamath Lake, famous for its fishing, and after running northward for about 20 miles along the eastern foot of the range it ascends the slope along the canyon of Anna Creek to the rim of Crater Lake.
The Klamath Falls route from Ager, Cal.—The approach from the east may be made also by a longer route, leaving the railroad at Ager, Cal., and traveling by stage road along the Klamath River, through the Cascade Range to Klamath Falls and Fort Klamath, from which point Crater Lake is only 20 miles distant by way of the Anna Creek road, already noted. The older tilted lavas of the Cascade Range dipping to the east are well exposed on this route at many points along the Klamath River road between Ager and Klamath Hot Spring.a Across the edges of these lavas, nearly 1,000 feet above the present river bed, is an ancient wide valley of the Klamath River, associated with gentle topographic relief at higher levels. Later lavas have crossed the range in this wide old valley and the Klamath River has cut a deep canyon in them. Within this young canyon, north of Bogus post-office, there has been a volcanic eruption, forming a dam across the Klamath and a consequent ponding of the river, in which a mass of white diatom earth was formed. The products of this eruption are much younger than any others known to the writer in the neighboring portion of the Cascade Range.
aThis celebrated health resort has a good hotel, fine scenery, hunting, and fishing.
The Rogue River route from Medford, Oreg.—From Medford the road by way of Rogue River, although 75 miles in length, is somewhat the shortest route. It affords some fine views of the canyons and rapids of that turbulent stream and of the high falls, where it receives its affluents, especially Mill Creek, below Prospect. A few miles below the mouth of Union Creek is a remarkable natural bridge of lava, but some distance from the main road. Striking features along the roads on both sides of the mountain, within 20 miles of the lake, are the plains developed upon a great mass of volcanic detritus filling the valleys. Across these plains Anna Creek and Rogue River have carved deep, narrow canyons with finely sculptured walls, which the roads follow for some distance.
The main road, whose grade is in general very gentle, crosses the summit 3 miles south of Crater Lake, and from the western slope near this point the crest of the rim is reached by a road with several heavy grades. There are good camping grounds with plenty of pasture on Castle Creek beyond the forks of the road and within 2-1/2 miles of the lake. At the end of the road, on the rim of Crater Lake, the camping places are fine, but pasture and water are not so abundant nor so easily obtained. There are as yet no hotels nor permanent accommodations for travelers at the lake, but during August and September, the most favorable months for visiting the lake, temporary accommodations should be provided and travel encouraged.