Report - - Port Mulgrave ironstone mine + tunnel, May 2015 | Underground Sites | 28DaysLater.co.uk

Report - Port Mulgrave ironstone mine + tunnel, May 2015


28DL Full Member
28DL Full Member
Living only ten minutes away from here and having read the report that Acid-Reflux put up last week (and that nearly ended in serious unpleasantness), I was stung into action. This is one place that I first visited a few years ago after reading a lot about it, but the portal was properly closed up so I'd pretty much given up hope of ever getting in here. Acid's report was awesome and made me want to get in there and see it for myself, along with my trusty Altair4 gas detector.

Acid's report: http://www.28dayslater.co.uk/port-mulgrave-ironstone-mine-tunnel-may-2015.t96433


If you've read Acid's report, you don't need much history. Suffice to say that my interest in this place stems from the fact that it's linked to Grinkle ironstone mine via the tramway tunnel (the western end is blocked off at Dalehouse) and Ridge Lane Tunnel (see my recent report on Grinkle). There is the odd trace of the industrial past evident as you haul yourself up from the bottom of the old harbour to the portal (some iron and brickwork) but the real treats are in store once you're inside. I also think I saw Acid's white facemask dangling from some shrubbery outside, but maybe that was just coincidence ....

The entrance hall


As soon as you get inside the portal, there's an immense roof collapse ahead before you get to the twin openings of the drift mine and the tramway tunnel that runs through to Dalehouse. There are big flakes of rock hanging from the ceiling here and water dripping insistently from the ceiling.
O2 levels at this point? 20.8%

Once over the specatacularly-coloured roof collapse, you're looking down at the twin portals:


The smaller tunnel on the left is the drift mine that was originally here at Mulgrave; that on the right is the tramway tunnel that runs through the hillside to Dalehouse near Staithes. The second you drop down to tunnel level, the O2 drops to 19.5%.

The drift

For those people who just love deep sludge, the first ten metres or so of the drift are heaven - sucking ochrous mud does its best to rip your footwear off (thank Christ I was wearing waders) and progress is pretty slow whilst trying to stop your camera and tripod dropping into the murk. The brickwork only lasts for those first ten metres or so:


There is the odd rock under the surface which tries to trip you and send you sprawling into the filth, which would be a pretty poor day out of it. I'm fairly sure this stuff wouldn't taste nice at all!

Once out of the drift tunnel, you're into the proper mine stuff where the passageway has been hacked and blasted out of solid rock. Colourful rock abounds but the slightest brush of my head on the ceiling if I stood too vertical was enough to cause the odd little shower of rock to drop down the back of my neck.


And the omnipresent river of ochre keeps you company with every step, waiting to suck you into to its sludgy depths.


The strata here bears a striking resemblance to that in some of the Hutton jet mines in Guisborough.

Up ahead, the roof gets lower, the sludge gets deeper and there's water everywhere. The oxygen at this point dropped further to 17% and I decided that I was already filthy enough and had no desire to get absolutely pitted and soaked to the skin. I really need a caving suit!


I may have to come back here more appropriately dressed and see how far the drift goes in from this point ...

Heading back out, I grabbed another shot as I approached the portal brickwork again:


The tramway tunnel

This is where it all went horribly wrong for Acid on his trip and, having been here, I can see why. Nothing gives away the fact that the O2 levels steadily drop (precipitously after the first huge roof collapse) and you could very easily end up in the shit here, being awed by the sight, by the handiwork of the engineers who crafted the tunnel and by the hypnotic sounds of rushing water.

It was only the shrieking alarm of my Altair4 (and the memory of Acid's close call) that kept me from exploring too far in here: I was desperate to see the point at which the lower level tramway splits from the upper level but didn't manage to get that far. If I hadn't had my Altair with me, I would probably have blundered on, intent on getting a shot of that fork in the tunnel ....


This is the view from the edge of the tramway portal - you can just see the left rail disappearing into the water (which is lower than it used to be, courtesy of some fine unblocking by a stalwart 28DL member) and the still waters heading off into infinty.


After you exit this first section of tunnel, the roof opens out and becomes something more akin to Sandsend or Kettleness rail tunnels - I'm sure there's a convincing engineering explanation for why the tunnel takes on so many different forms at this particular section, but I was more interested in the O2 levels, which dropped to 18.3% as soon as I entered the tunnel itself.


Up ahead, you can see the huge collapse that has left a massive void in the roof. And that, ladies and gentlemen, is as far as I went - leaving my camera at this point, I headed off up the tunnel, over the collapse and into the void. At that point, the Altair went berserk, O2 levels dropped below 15% and, with the warning words of Acid-Reflux ringing in my ears, I headed back.

As I worked my way back along the tunnel to the entrance, I grabbed a few more shots of the smaller details that I hadn't seen on the way in: a roller wheel, insulators in the tunnel roof, the adit that drains the tunnel into another small drift .....





Back at the relative safety of the first collapse, I got some more shots of the twin portals, the immense calcification that's gone on where the roof collapsed and the entrance to the system itself:




This is a place that's going to niggle away at me until I go back, man up and explore further past the collapse in the tramway tunnel - Acid's report shows that's where the fork in the tramway is, but also where it started to go wrong for him. Given that 15% O2 content is roughly equivalent to being at 2000m altitude, I suspect it gets very bad further on past that collapse so might need to look at some form of BA in order to get further in. Anyone know someone with any they can lend me? :confused:

Thanks to Acid-Reflux for his fantastic report that got me fired up about this place again and for his pictures (especially that one of the tramway fork that will now haunt my dreams).

... and thanks to you for reading!


The Wombat

Mr Wombat
28DL Full Member
wow, this is a stunning report
good write up, excellent well lit photos, and a really interesting place.
Well done for persevering as far as you did in difficult conditions :thumb


28DL Full Member
28DL Full Member
Acid did all the hard work - I just followed in his footsteps (well, you know what I mean). Looking back at his report, the tramway fork was only just past the roof collapse ...... grrrrrrrrrrr.


28DL Full Member
28DL Full Member
I just knew you were going to risk it mate & i"ll tell you what reading your report my heart rate was increasing rapidly as i progressed through with you.......weird or what ?

I think i was expecting the worst for you & you"d have an incident....thankfully not & my pulse can lower itself again.

Although i must admit i"d like to know what the 02 readings would have been in the 3rd tunnel section @ the complete blockage area, well percentage wise i already know it"s not enough to sustain an old bloke ;)

Nice pics BTW :thumbthey remind me of someones :D and yes i did a good job of lowering the water level, unfortunately that"s what"s kept a lot of people out of the tunnels.......and the multiple roof collapses of course ;)

TBH the 2nd tunnel section is the end of the interesting bits showing the lower level tramway spur as you know but i don"t think i"d return even with my Air Tanks as those roof collapses are just too risky.......in hindsight obviously.

I"m just afraid of however tries it next is as stupid as i was :wanker

We"ll have to have a another chat mate :thumb oh & thanks for the publicity ;)

I should add i couldn"t use the FP3 mask i had round my neck, i found breathing too restrictive :eek:
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Dockers Umbrella
Regular User
nice stuff Mate :thumb

the tunnel closed in 1934 & its identical too my 2008 visit,
so the risk of a collapse while your there 100,000 too 1.
My concerns the air,
so I will definitely be using a moniter & O2 cylinder/mask on returning.

well done both you & Reflux for doing this


28DL Full Member
28DL Full Member
I'd be back in there tomorrow if I had some BA to combat the low O2 past the big collapse. Maybe even dig out the total blockage in the tramway junction and further in. It's got me .....


28DL Full Member
28DL Full Member
I'd be back in there tomorrow if I had some BA to combat the low O2 past the big collapse. Maybe even dig out the total blockage in the tramway junction and further in. It's got me .....
It"s the only Tunnel i"ve ever been in where there"s no air movement noticeable. Normally you have the small calcite particles etc drifting about in the air...... nothing in here even after intentionally bringing roof sections down didn"t raise dust. Another warning !

And i will reiterate Stranton, the roof over the collapses was still shedding lumps of rock even before i knocked it.


28DL Full Member
28DL Full Member
There was load of stuff in the air yesterday: far more than in Sandsend tunnel. Surprised me to be honest as I was expecting it to be pretty dead in there. Should have worn a mask to be honest as I've been emptying loads of muck out of my nose and lungs this morning .... o_O


Poking holes since '84
28DL Full Member
Excellent work there. Really enjoyed reading your accounts of this and the associated history, not to mention the quality of the pictures too :thumb

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