Bishop in the pipe in Aliens?
I did that when I was ten.

It lead to one of the two sketchiest places I've been in my life.

When I was a kid I lived in Bolton, on Catterall Crescent.
At the top of the Crescent there's a ginnel.
The ginnel leads to the top fields...

Ginnel is Yorkshire/Yorkshire for alley way. It comes from the old English "Ginn" meaning "an opening, or Abyss"
And it did lead to an abyss.
The top field's still there, I see, on Google maps and as often was the case back 30 years ago the grass is dead...

The top field is man made and flat as anything. Or was back then. The trees weren't there when I was a kid.
It was great for football and cricket.
Flat and featureless apart from the hatch.

The iron hatch in one corner which the big padlock...

Under the field was an underground reservoir.
It was pretty much a giant concrete box with enough water for the estate.

One day refurb work started on it.
The work men opened up the little pump house that used to be where that dark circle is now. (the smaller feature)...

The pump house (which doesn't look to be there anymore) was set into the side of the hill.
I'd been in it a few times. Older boys would break in from time to time.
Inside there was little more than a pipe. A 90 degree bend that came out the wall and went in the floor...

A proper fat pipe though...
Anyhow, the workmen were doing something with it during the week and on the week end I got in again and this time the 90 degree bend wasn't there.

This was the middle of one of those long hot summers but in that pipe was total and complete darkness...

So I ran home for my torch. Because kids had torches back then.
I returned & a did the Bishop crawl through the pipe.
I got into the underground reservoir.
They'd drained it for whatever they were doing.
Well... drained it as well you can. A thing like that.
It was huge inside...

There were a few inches of water left in the bottom. The splashes echoed.
The whole thing was a massive echo chamber.
The coolest thing was the crappy kid torch would light stuff near me. The wall and the water but couldn't light the far wall.

So I went there...

I went to the opposite corner.
It was exactly the same as the corner I'd just come from.
Featureless concrete wall, but high above me a chink of light.
The hatch I mentioned earlier.

Then for no reason a wave of fear washed over me.
What if I couldn't find the way out?...

I was suddenly terrified.
Who's to say the floor was flat? There could be some other pipe in the floor along the way just under the water. I may have just missed it. If I fell would anyone ever find me?
The men could come back and fix the pipe.
I was properly scared & I loved it!

Anyway... I did get out.
It seemed a longer walk back to the pipe and there was a freaky bit where I got to the bit of wall the pipe should have been in and it wasn't there... turns out it was just a bit further along.

And the Bishop crawl out into day light felt longer too...

And that was one of the the two most sketchiest places I've been in my life...

The other place... that's inside the house I live in now.

But I'm tired, so I tell you that tomorrow...

...so. Morning.
This is the cupboard under my stairs...

We keep skateboards and bike pumps in it. So because kids it's not unusual to find it open.
So we close it.
Anyhow, one day my wife announced she wanted a new radiator in the lounge.
Something fancy and new.
So we got one and I plumbed it in. Here it is...

It's not that easy.
It's a new standy upy radiator, so a third the width. It didn't fit on the old pipes.
Nightmare.
Change a radiator the same size, just isolate the rad & swap.
Different size means new holes in the floor and cutting pipes. Which means draining the system...

So having drained the hearing system and drilled new holes for where the light of my life wanted the radiator it was time to get under the floor so I could replumb the pipes to go up the new holes.
To do this I have to go in through the loose floorboards under the stairs...

So you've got to crawl in the cupboard under the stairs and... disappear
My house is 120+ years old. So no damp course. No concrete foundations under there. Just dirt.
Under the stairs is in the back half of the house. I had to do my plumbing at the front.
Which means crawling...

Crawling though the house's central supporting wall. (The solid wall in the middle of your house that holds it up).
I've just stuck my arm down the hole under my stairs there's the supporting wall we have to crawl though.
That blue is a skipping rope holding up wires and pipes...

This isn't a hole for made for crawling though. Someone decades ago broke though... probably to install central heating.
It's a tiny hole.
You can't crawl though hands and knees.
You can't even get through lying flat you have to do it on your side...

Moreover there's not enough room for your arms and body. You have to put your arms through first, and lying on your side, find purchase in the dirt with your feet to scrape your body through.
And I do mean scrape.
Bricks rubbing on your back and stomach...

All the while tring not to mess with the pipes and wires that also travel through that hole.
In short. Having gotten though you can't be sure you'll be able to get back through.
You can't be sure you'll get out...

So I did the plumbing and I did get back out.
I re-pressurised the heating system and switched on.
It worked. I'd done it.
Lovely hot radiator... nice!

But...

couple of days later I noticed a serious loss of pressure in the system.
It was obvious. There was a leak...

BECAUSE I'M NOT A PLUMBER!
The missus and kids were out for the day so I though "Screw it! Get under there now. Sort it.

I didn't even bother pulling out the skateboards from the cupboard under the stairs. Just squeezed down through.

And again through that tiny hole...

and... there was no leak!?
I couldn't understand it. but it was time to get out.. maybe get a grown up on the job.

Anyway, that didn't go well...
..............................
I've just got to walk the dog... be back in about half an hour...