Our hikes to the Temescal / Cajalco Tin Mines: Riverside / Corona
Back in July 2017, my wife and I went for a short hike in the hills above La Sierra near Lake Mathews. When we got to the top of the first hill, we decided to abandon our planned hike and go in a different direction. A few miles later, we decided to see if we could make it to Corona Crossings. Six or seven miles later, we met our kids at Chick-fil-A for a well-deserved lunch.
Completely by accident, we ended up hiking through the site of the old Temescal / Cajalco tin mines.
I’ve been back out there a bunch of times since our first visit. Here are some pictures:
On our first hike, we found these burned-up cars in a clearing a few miles in from where we started on La Sierra. The cars are gone now, but this is a popular spot for illegal target shooting. I’ve walked through here three times when people were out shooting. Be careful if you venture through here.
I like stopping here for a moment to take in the view. There have been two recent fires in this area. The first picture is from July 2017 and the second is from April 2018.
On to the old tin mining site…
This is a picture from “about 1890” of the tin mining site from a Press Enterprise article:
I hiked back out there today to see if I could get a current picture from the same perspective:
According to a post on the History of Corona Facebook page (follow the link for a summary of the history of the tin mines), the tin mines closed in 1892. There are also a few old pictures attached to the post, including this old map of the site:
Here are some pictures of the remaining structures…
Reservoir?
Ore bin?
Smelter? By the way, there is now a big red bullseye (actually, a painting of a ladybug) on the large concrete structure in the middle of the picture. In addition to the clearing I mentioned above, people also use the tin mining site for illegal target practice. I’ve seen or heard people shooting out here a few times, so be careful.
There used to be a large structure at the top of this retaining wall.
You can see this retaining wall toward the bottom right of this picture posted on the History of Corona Facebook page:
If you walk up the steps, watch out for the barbed wire on the ground.
Looking down the steps.
Remnants of another structure.
There are three fenced-off mine openings in the immediate area. Here are a few of them:
This old structure…
… appears to be one of the buildings near the right of this picture from Corona Public Library’s website:
I’m always on the lookout for wildlife when I go on my hikes, and was surprised to see this guy out at the tin mines back in November of last year.
Update: April 2020 – My wife and I also saw this guy or girl near one of the mines. We think it is a red diamond rattlesnake.

This hill is to the west of the tin mining site. Although I don’t know the actual name of the hill, I call it “Tin Hill”. The flag is a new addition that we noticed on a recent visit.
I hiked to the top of this hill back in November 2017. The side I climbed is covered in loose rock and I almost fell a few times. There is actually a path on the other side of the hill. Oops.
The view of the old tin mining site from the top of “Tin Hill”:
By the way, bring plenty of water. I let myself get in trouble once on a very hot day out here. Thankfully, a freak thunderstorm saved me.
Looking for more hiking spots in and around Riverside? Check out our list of Places to Hike in Riverside and Beyond. #hikeriverside
Great Information and very nice job putting it together!
Really cool! My dad and I visited here a few months ago and hunted around for some interesting rocks and minerals since I want to be a geologist and have a passion for rocks. I am now completing a school project on the mining history and geology of this place. Thanks for the info!!
Hi there future geologist! Hope your project turns out great.
Great pics! I like seeing the original views and the current views simultaneously. I always want to stop and explore remnants of old buildings and homes and rarely have the time to. Here, you did it for me. So, thank you!
Thank you!