Cajon(es) Pass - The Origin of the Name and a Little History
Somehow the question came up recently about the etymology of Cajon Pass. Several of the Spanish speakers in our group were dismissive of any possible association with ‘cajones’ and promoting the meaning of cajon as ‘box’. But, why would it be known as ‘box’ pass? Here is what a little research revealed.
Modern day Cajon Pass from the air
As it turns out, it is indeed cajon as the Spanish word for ‘box’ that was used to describe boxlike canyons. The original name of Cajon Pass was el cajon que llaman Muscupiavit (the canyon that they call Muscupiavit), as it was referred to before 1806, Muscupiavit being an Indian rancheria, the name of which has been spelled in various ways. On November 24, 1819, Padre Nuez named it solemnly el Caxon de San Gabriel de Amuscopiabit, the name appears in the following decades with various spellings. The abbreviated form Cajon Pass, is used on Gibbes' map of 1852. The settlement of Cajon was laid out when the California Southern Railroad (Santa Fe) began operations through the pass in 1885, but a settlement of that name had already appeared on Williamson's map of 1853.
As backpackers know, Cajon Pass is the valley that separates the San Bernardino and San Gabriel mountain ranges, two significant chunks of the Southern California PCT (Section C and Section D). At one time these two ranges were one, formed by the San Andreas fault where two continental plates, the North American and the Pacific plates push against each other. As the years passed a low point eroded by water and helped along by additional faulting formed the valley between the two. It serves as a passage between the high Mojave Desert and the inland valleys and basin.
Certainly early on man found his way through the pass in one direction or another in his wanderings many thousands of years ago. The Indians, the Serrano in particular, knew the valley well and lived there for hundreds, maybe even thousands of years before the first European ever found his way into the area.
It may never be known, but possibly the first white man to enter the passageway between the two lands could have been a deserter from the Spanish Army. What is known is that Pedro Fages, who was destined to become the Governor of California, was the first to pass through in search of these men. Fages rode through the area coming from the south and soon after discovering and naming the San Bernardino Valley. He did not spend long in this place.
Padre Francisco Garces came soon after at the end of his 1775 crossing of the interior Mojave Desert. Some reports claim Garces crossed through one of the mountain passes to the east and others have him descending the pass into the Southern California area. Next was mountain man Jedediah Smith. As trade developed the route became known and more and more the Pass was used. The Indians became absorbed into the missions.
Maintaining a wagon road over the Pass was a difficult job. Eventually a toll road was constructed. The toll road, however became quite controversial and people found ways to bypass it. The railroad came through the pass in the 1880s. This was a faster more economical way of moving goods to and from the rapidly growing state of California.
The toll road eventually became the alignment for a paved road as automobile travel became more frequent. This road was called the National Old Trails Highway which in turn became the U.S. Route 66. A cut in the grade to the summit of the Cajon was made and eventually widened to accommodate State Highway 91. In later years the highway was widened again and became what we know today as the Interstate 15 Freeway.