people also developed a food processing site with numerous mortar holes in the sandstone rocks still evident— or formerly evident until CalTrans closed the access road for safety reasons. The watercourse that seasonally flows through today ' s center median of the highway had to be diverted through underground culverts. This creek channel was prehistoric, and it became a nuisance to the waves of new settlers. The nearby creeks would coalesce into a basin that formed a peat swamp. So travel through the Pinecate Rocks was unreliable, except for the Native people who would always negotiate the terrain on foot. The engineering challenge required the construction of a stable roadway foundation by draining the peat bog and elevating the surface with fill.
The Prunedale Cutoff was opened to traffic on July 20, 1932, upon the completion of a dedication ceremony, and was featured in the August 1932 California Highways & Public Works. Photo credit: Challenger Tom-Gribblenation January 01, 2023.
“ The Pinecate Rocks,” became part of US Route 101 when the highway was realigned past them, July 1932. Near Salinas, San Benito County. Photo credit: Challenger Tom-Gribblenation January 01, 2023
No doubt, the geology of the area, with the San Andreas Fault so close by, dictated some precise engineering. The Pinecate Rocks continue to move toward the northwest along the San Andreas faultline. Quite a variety of rocks were in the area. For example, the nearby Wilson Quarry, owned by Granite Rock in Aromas, has been crushing granite rock for more than 125 years. In addition, the extensive eucalyptus grove near the Pincate Rocks had to be partially cleared. Eucalyptus trees were widely planted in California during the late 1800 ' s by early settlers, including in the Aromas area, perhaps as a source for future lumber sales. Today the trees are being removed because of their fire danger and the occasional tree falls that endanger vehicle traffic.
One of the largest boulders at the Pinecate Rocks had a staircase of footholds excavated into the rock that were used by robbers who would prey upon travelers, especially during the Gold Rush. Today, as we speed by, this small patch of rocks may not seem of much historical interest. Recently though, the Land Trust of Santa Cruz County acquired the Rocks Ranch as a wildlife corridor between four adjacent counties of Monterey, San Benito, Santa Clara and Santa Cruz. And in 2023, the San Benito Agricultural Land Trust was involved with the purchase of 521 acres of the adjacent Rancho Larios and the 540 acres of the Nyland Ranch. This full circle story concludes with the Amah Mutsun Tribal Band serving as land stewardship partners for these properties through cultural easements. The First Peoples are returning to their home landscapes.
Notes: US Hwy 101 has a long and well documented history. A vast database of images curated by various sources.
For further study:
CalTrans Transportation Library digital Collections: Caltrans McCurry Collection
The Internet Archive( see story in this issue) https:// archive. org /
A great social media group: Facebook / California’ s Historic Highways
gmhtoday. com Gilroy • Morgan Hill TODAY Magazine: Go. Make history... WINTER 2026 41