Coquina is a specific form of limestone that consists of shell and coral fossils. It has many uses, including reservoirs for oil and natural gas, aquifers for groundwater, and building materials. And from 1929 to 1935, the Tapo Alto Shell & Fertilizer Company mined for this mineral in the hills of Simi Valley. While operations have long since passed, visitors can still find remnants of this forgotten operation. Which, on a spring Saturday morning, is exactly what we set out to do.
While this trail has no parking lot, street parking is bountiful and easy to find. Note that this hike starts in the middle of a neighborhood, so please be considerate of those who live in the area. There are also several trailheads in the area, so when you’re ready to go, head toward the paved road with a metal gate. There, you’ll also find an information sign, a picnic table, and a trash can.
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Starting our hike on the Las Llajas Canyon Trail. Shot on FujiFilm Superia X-TRA 400 film.
You’ll start hiking along the initially paved Las Llajas Canyon Trail and reach a junction almost immediately. Turn right to stay on the correct path. Soon, the trail turns into a wide, dirt road and you slowly start hiking into the heart of the canyon.
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Pretty soon the concrete road gives way to a more traditional dirt trail. Shot on FujiFilm Superia X-TRA 400 film.
At mile 0.4, you’ll start to hear and see a stream to your left. And if you haven’t already, you’ll soon run into other hikers and mountain bikers. However, because the path is so wide, there shouldn’t be any issues sharing the trail with others.
The deeper you get into the canyon, the more idyllic it becomes. When we hiked this trail, the sea of green grasses that covered the hillsides and the churning of the nearby stream felt straight from a dream. While we were tempted to stop our hike early and just enjoy the serenity around us, the Coquina Mine was still our ultimate destination so we pressed on.
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Las Llajas Canyon. Shot on FujiFilm Superia X-TRA 400 film.
About three-quarters of a mile into your hike, you’ll see bee hives on your left. Don’t worry, they are far enough away from the trail to disturb hikers. Then, just a few paces further is what appears to be a rusted trolly car to the right. You’ll encounter a few shaded spots as you continue to meander your way along the mostly flat trail through the canyon, but it’s mostly exposed, so make sure to bring sun protection and plenty of water.
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Several bee hives a safe distance from the trail. Shot on FujiFilm Superia X-TRA 400 film.
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While we couldn’t pinpoint exactly what this was, it looked to be a vehicle of some kind. Shot on FujiFilm Superia X-TRA 400 film.
You’ll have a few simple water crossings 1.4 and 1.7 miles into your trek before reaching a trail junction at mile 1.8. Turn left to leave the wide trail and start hiking uphill on a small, single-track path.
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The river crossings are easy, but depending on the water levels your shoes may get wet. Shot on FujiFilm Superia X-TRA 400 film.
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Leaving the wide path for single-track trail. Shot on FujiFilm Superia X-TRA 400 film.
The incline noticeably increases here as you slowly climb the west canyon wall. Along the way, we noticed several blooming plants, including California Sagebrush, Hoaryleaf Ceanothus, and the infamous Black Mustard. As you get higher, you’ll also start to see the trail cut out of the side of the mountain in front of you.
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Head right at this trail junction. Shot on FujiFilm Superia X-TRA 400 film.
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The higher you climb, the better views of the Santa Susana Mountains become. Shot on FujiFilm Superia X-TRA 400 film.
At mile 2.3, turn right at the trail junction. It’s here when the views start to truly open up. From this vantage point, you can see the grass-covered Santa Susana Mountains in all directions, as well as Simi Valley homes to the south. Overall, this part of the trail is serene – aside from the occasional mountain biker.
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Rusted mining equipment. Shot on FujiFilm Superia X-TRA 400 film.
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Another relic of the abandoned mine. Shot on FujiFilm Superia X-TRA 400 film.
Continue for a few paces to find your first piece of old mining equipment. A half mile further and to your left are more rusted remnants. At mile three, you’ll reach the start of a short loop. We headed right and quickly reached an impressive lookout spot before reaching the largest artifact yet – a mostly intact P&H Model 206 power shovel. The scene was frozen in time, with the earth partially carved out and the excavator stuck mid-scoop waiting patiently for its operator to return. It was as intriguing as it was eerie.
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The surprisingly well-preserved P&H Model 206 power shovel. Shot on FujiFilm Superia X-TRA 400 film.
Once you’re finished exploring the site, continue to complete the loop and retrace your steps back to the trailhead.
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You can see Simi Valley homes in the distance. Shot on FujiFilm Superia X-TRA 400 film.
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The Santa Susana Mountains were vibrant in the spring. Shot on FujiFilm Superia X-TRA 400 film.
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Hiking back to the trailhead. Shot on FujiFilm Superia X-TRA 400 film.
Tags: Coquina Mine, Historical Interest, Marr Ranch Open Space, rivers, ruins, Ventura County