I didn't go poke around, but took a few pictures on the way past.







some other old buildings nearby, I suspect also mining, not sure if mercury or something else



and a circa 1880 bridge that's on the way there

Mmmm, cinnabar
Like those crazy distillation pipes; note the liquid drains on the bottom loops.
I've visited two cinnabar mines here in Texas.

not a big surprise but apparently it's deteriorating at a decent rate. street view from 2013 shows it significantly more intact:



I also realized the photo I posted was from a previous trip, late 2017, rather than last weekend. oops. I don't see any huge differences from then.



maybe sometime I'll go back and poke around inside, but it's a LONG way from anything so if anything happened it wouldn't be good. I'm not sure who owns it, likely a power company - there's certainly a lot of land on that road owned by various power companies.

I've been to some of the mercury mines in San Jose. Most have the entrances full of rocks and rubble. Kinda interesting...but more just a place where kids were drinking.

But you're right, it can be dangerous. Because I had weak batteries in my flashlight I almost walked right into a DEEP pit. How deep, no idea, but couldn't see the bottom even with my friend's better powered flashlight.

But this was 20+ years ago and I'm guessing by now they're closed up.

Posted by totensiebush not a big surprise but apparently it's deteriorating at a decent rate. street view from 2013 shows it significantly more intact: https://i.imgur.com/BWtNyFX.png I also realized the photo I posted was from a previous trip, late 2017, rather than last weekend. oops. I don't see any huge differences from then. https://i.imgur.com/D9kKZsC.jpg maybe sometime I'll go back and poke around inside, but it's a LONG way from anything so if anything happened it wouldn't be good. I'm not sure who owns it, likely a power company - there's certainly a lot of land on that road owned by various power companies.

Do it. This is a rare and unique site.
Be careful as hell; trust -nothing-
Eyes open on the ground for hellholes including vents for the mine.
This is probably the most intact mercury distillery stateside.
Magnificent.

The one I was on used 36 inch glazed terracotta pipes, T's and elbows but was in complete ruins.

Wish I was closer. That could be a great explore. Always love to head underground.

Abby Normal

I put it in the DB for anyone who wants a location.

What’re the chances of this place having any intact tunnels that you could actually get into?

Posted by SirTopRamen What’re the chances of this place having any intact tunnels that you could actually get into?

Good. The two I saw in TX did.
It might be your last explore... probably been abandoned for 70+ years.
Even with proper gear and skill it most likely be very dangerous.
On the bright side if entombed in cinnabar it might mummify your body
Best to leave sleeping bats lie...

Posted by SirTopRamen What’re the chances of this place having any intact tunnels that you could actually get into?

No clue. I don't even know if the mining here was tunnels or pit/strip. There's some evidence of pits in the area, but it doesn't look like enough given the extent of facilities... but maybe it's just overgrown.

A mercury mine site I've been to in SLO county has tunnels that access has varied on: when it was a superfund site it got sealed up with foam, people burned it out, they collapsed the entrances, people went in the open top that can't reasonably be filled, etc. So there's a decent chance they've tried to stop access if there's anything there.

Access to the buildings on the other side of the creek isn't going to be safe as far as the law goes: there's a locked gate and then a walk of a little over half a mile. There's nowhere to park a vehicle without anyone who drives past immediately noticing - this is seriously in the middle of nowhere, on a one lane road with some gravel sections, 10 miles from the nearest town. Given that street view has driven past I'm not too worried about posting hints, but don't want to make the location itself public.

I think the remoteness is a major part of why this is as intact as it is, as it isn't *that* far from big cities (google says you could get there in an hour).

Blackhawk, from what I've read there was mining going on there until the 70s.

70's? Could be true.
WW1&2 created the high demand for mercury for ammunitions.
Due to its toxic nature and lower post war demands its principal production migrated to 3rd world countries.
Apparently it was last produced stateside from ore in 1992.

Great shots and super cool site! Even just the location looks beautiful. Going in seems enticing but I'd be pretty cautious. I'm sure open shafts/vents could be a big hazard, but I'd be more scared of mercury exposure. Does anyone know if old mercury residue in a mine could still be a hazard to explorers after a few decades of disuse? If so, what sort of protective gear would one need? A site like this looks like a gold (er, cinnabar) mine but mercury poisoning seems pretty miserable.

My understanding is that cinnabar itself isn't too hazardous, especially as a one time exposure thing.

The processing equipment, tailings piles, etc can absolutely be.

I've been inside another mercury mine with a bunch of UERers (and I think there was even a reporter), the one I mention in SLO county. My impression is that the abandoned mine part is far more hazardous than the fact that it's specifically a mercury mine.

Posted by Ptasteful_Pteranodon Great shots and super cool site! Even just the location looks beautiful. Going in seems enticing but I'd be pretty cautious. I'm sure open shafts/vents could be a big hazard, but I'd be more scared of mercury exposure. Does anyone know if old mercury residue in a mine could still be a hazard to explorers after a few decades of disuse? If so, what sort of protective gear would one need? A site like this looks like a gold (er, cinnabar) mine but mercury poisoning seems pretty miserable.

Elemental mercury isn't a hazard unless heated and vaporized and inhaled; bp 674 F.
Cinnabar is composed of mercury sulfide which is almost completely insoluble in water.
Seems to have a low toxicity.

However if converted to a sulphate or oxide they are highly toxic. The roasting of cinnabar may have created these and other mercury compounds as well.
Best to not stir up dust or build fires at these sites.

Posted by blackhawk Best to not stir up dust or build fires at these sites.

So you're saying keep PG&E away? Isolate & deny entry tactics?

Posted by RescueMe1060 So you're saying keep PG&E away? Isolate & deny entry tactics?

LMAO
More campfires; only takes a very small amount of mercury vapor to ruin your life.

Very cool location - I've been by here twice in the last few years and this is about the same extent I've explored. Once by bicycle, once by car - there was a spot that was very hidden from the main and only access road in both directions. The chances of anyone rolling by is rare, but any activity here at all would attract attention.

If you look up older USGS topo maps, you'll see a huge concentration of mines in this area. There is an adit visible nearby on this same slope but I can't speak to its accessibility or safety.

That bridge also has some history. And if you go over the summit north to south, there's hell of a view.

I haven't been on here regularly for some time but this immediately had my attention. It's a very interesting area no matter how much is practically accessible here.

Yeah, the bridge was originally built around 1880, most likely in Texas (well, manufactured in PA, originally used in TX). In 1909 or so, it was moved to Monte Rio. In the late 30s, it was moved to it's current location. There are 2 other very similar bridges from the same project still in use in the area: Haupt Creek (on Skaggs Springs-Stewarts Point Road) and Gualala. The other two are more original: they retain the cast portal bracing, rather than the fabricated bracing on this one.

I'd be interested in looking at the more hidden site as well, could you PM me a location?

There's also the old town site, with the name on it, but it appeared people were living there so I didn't go in. There's another couple current residences on the road as well.

Looking on google maps I see various locations where it's obvious there is/was something (some more is, some more was), but I have no idea whether most of them are old enough to be mining or if they're from the power company.

There are also several places on the road where it's clear there used to be bridges, and the foundations are still there, but they moved the road and no longer used them. There's a LOT of history in the area.

Posted by totensiebush Yeah, the bridge was originally built around 1880, most likely in Texas (well, manufactured in PA, originally used in TX). In 1909 or so, it was moved to Monte Rio. In the late 30s, it was moved to it's current location. There are 2 other very similar bridges from the same project still in use in the area: Haupt Creek (on Skaggs Springs-Stewarts Point Road) and Gualala. The other two are more original: they retain the cast portal bracing, rather than the fabricated bracing on this one. I'd be interested in looking at the more hidden site as well, could you PM me a location? There's also the old town site, with the name on it, but it appeared people were living there so I didn't go in. There's another couple current residences on the road as well. Looking on google maps I see various locations where it's obvious there is/was something (some more is, some more was), but I have no idea whether most of them are old enough to be mining or if they're from the power company. There are also several places on the road where it's clear there used to be bridges, and the foundations are still there, but they moved the road and no longer used them. There's a LOT of history in the area.

Is that a Phoenixville Steel bridge?
They were a prefab "kit" bridge with a long lifespan.

it's a Phoenix Iron Works bridge (and yes, from Phoenixville PA)