232 Adventures in Scenery 



The range has been raised between faults on the north and south 

 sides. To the north is the Mojave Desert. On the south the 

 range is bounded by the western portion of the Colorado Des- 

 ert, the San Gorgonio Pass, and the San Bernardino Valley. 

 The range as a whole is a vast uplifted block. It is, however, 

 broken by many faults, so that the range may be said to be 

 made up of a considerable number of "horst" blocks. San 

 Gorgonio Pass is a sunken valley, technically called a "graben," 

 between the San Bernardino and San Jacinto mountains. 



The general "floor" of the top of the San Bernardino Range 

 is in marked contrast to that of the San Gabriel Range, which 

 lies immediately to the west of Cajon Pass. The San Bernar- 

 dino upland surface is marked by broad comparatively level 

 plains with many old rounded hills, whereas the San Gabriel 

 upland is all cut by deep gorges and canyons which are sepa- 

 rated by sharp knife-edge ridges with no flat tops or plateaus. 

 Throughout the western end of the San Bernardino Range there 

 is a strikingly level sky-line at an elevation of 5,000 feet or 

 more. There are many broad meadows, with lakes and playas, 

 separated by smooth ridges. The central part of the range, a 

 few miles to the east, has a general elevation of 7,000 feet, and 

 the surface outline is that of a subdued worn-down old-age 

 region, a rolling plain with rounded hills and broad meadows. 



Standing high above the general plain are two outstanding 

 peaks, San Gorgonio, 11,485 feet, and San Bernardino, 10,500 

 feet. A long even summit ridge extends from San Bernardino 

 Mountain to San Gorgonio Mountain. From these two promi- 

 nent peaks the highest ridge of the range extends westward to 

 Cajon Pass. The summit of San Gorgonio Mountain is gen- 

 erally flat except for knobs of granite, boulders carved by wind- 

 driven sand into fantastic shapes, and pinnacles of granite 

 boulders resembling crude monuments made by placing one 

 stone above another. San Bernardino Mountain culminates in 

 a serrate ridge, but half a mile to the east this changes to a nar- 

 row flat summit, and half a mile farther this broadens to a con- 



