Jamul Kiln Ruins

Hidden among some low grassy hills in San Diego County are the ruins of the Jamul Kiln, or Jamul Cement Works. I learned of this site while researching interesting and historic places to hike to around San Diego.

"A little more than twenty miles southeast of San Diego, within the boundaries of the Mexican land grant Rancho Jamul, a curious and substantial masonry structure stands isolated at the foot of a low hill. The structure houses two octagonal kilns, a brick smokestack rising more than thirty feet above them. Limestone and clay from a deposit on the hill behind were once burned in these kilns by the Jamul Portland Cement Manufacturing Company, an enterprise created during the boom of the 1880s." 

San Diego Historical Society: Jamul Cement

The Jamul Cement Works soon after its abandonment. The trolley tracks to the limestone deposit on the hill are directly behind it. The masonry kilns occupy the center behind the lumber shell. The buildings on the right house the boiler room, the brick machine, the grinding apparatus and the workers' living quarters. To the left are the five pot kilns.

I'm always up for an adventure in the wilds so when I first learned of these ruins I knew I had to find them for myself. After a little internet research and consulting my maps, I found the site within a few minutes. So after making arrangements with my friend Steve and his girlfriend Tammy, we were headed out towards Jamul on a Sunday afternoon.

Passing some relatively modern pipes and industrial materials. We knew these came from the ocean since they had barnacles attached to them.

Our first sighting of the ruins. Construction of the cement plant began in April of 1890. The kilns were fired up in March of 1891.

 The organizers of the Jamul Cement Works had hoped to eventually produce 1000 barrels (200 tons) of cement per day, but the daily capacity of the plant was reportedly 150 barrels. A crucial spur to the nearest railroad  was not built, and it cost about as much to haul cement by wagon the dozen or so miles to the railroad at Sweetwater Valley as it did to ship it around the Horn to the Bay. Labor costs were also high. 

The building boom in Southern California had subsided, and the nation as a whole was headed towards the Panic of 1893. Any financial support for the improvement of the Jamul Cement Works dried up.

By 1906 most of the plant was dismantled. By this time, the California Portland Cement Company at Colton and other large plants were in production, and the Jamul deposit was not only too small to be profitably developed but still lacked a railroad spur. 

Although cracks have developed and firebricks are missing from the linings, the kilns have stood largely undisturbed since 1891. Because of their primitive design they might prove to be the only ones of their kind still standing in the United States.

Click here to see a photo of the kiln from 1918. San Diego History Center

Making our way back to the trail head.

This is an awesome site. The large brick ruins are graffiti-free and seemingly untouched by modern man. As for sharing directions to this site, my thoughts are in line with those of The Last Adventurer, who also posted a great write-up on his search and discovery of these ruins. Here is a partial quote from his blog:

 "...after finding it, and after spending some time at it, I felt like I would be doing the site – and its history a disservice if I was to post directions to it. While I know it’s not my job to be the gatekeeper for this – or any site, I do feel strongly, as I did about the Blue Sun Cave, that I do have a responsibility to protect these areas for future generations and explorers. I feel like I would be remiss if I blindly posted directions to these sensitive sites; and I feel like I would be further remiss if I allowed intentional – or accidental harm to come to these sites." -THE LAST ADVENTURER

Click here for his blog post.