Does anyone know the longest (from an entrance) point one can reach in the UK / in the world?
There's a cave in America, Fort Stanton Cave ( Snowy River Passage), with a point over 12 miles (19.3km) from the entrance:
https://plus.google.com/u/0/100434312839264796873/posts/BksKzMmcPP2

I've done a few statistics with Thomas Holder's python interface to survex on the (open) Draenen data:
https://gist.github.com/jarvist/5657022

OD2 entrance.20 <>  luck3.19
Shortest Path (m): 5325.59207671
Shots in Path:  494

OD2 entrance.20 <>  pow.44
Shortest Path (m): 4702.71359757
Shots in Path:  445

OD2 entrance.20 <>  rifleman.1
Shortest Path (m): 3375.00161578
Shots in Path:  281

OD2 entrance.20 <>  wiggly2.1
Shortest Path (m): 2507.04096711
Shots in Path:  210

Are there any other data out there that might beat this? Is there a Daren .3d anywhere abouts?

I'm assuming this is a measure of remoteness, the shortest surveyed distance between the far point and the nearest entrance, regardless of the reasonableness of the route.  We had once thought that Castleguard Cave, at 8.9km, held that record, and maybe it did for awhile but it is something that was not commonly calculated amongst long single-entrance caves.

jarvist said:

Is there a Daren .3d anywhere abouts?

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There is but my version doesn't have the Psychotronic Strangeways-Encillio Passage -Borrowed Boots Streamway on it.  Since Daren Cilau has four entrances and the nearest one to the end of Spaderunner is actually the resurgence in the Clydach your calculation might not be relevant to the majority of cavers.

ian mckenzie said:

I'm assuming this is a measure of remoteness, the shortest surveyed distance between the far point and the nearest entrance, regardless of the reasonableness of the route. 

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Scaling very roughly from surevys in Limestone and caves of Wales, other south Wales 'remote points' include:

Ogof Agen Allwedd: Ogof Gam entrance to Sump 4: 3.5km
Ogof Darren Ciliau: Pwll y Cwm to Friday 13th: 3.2km
Ogof Darren Ciliau: Ogof Darren Ciliau entrance to Friday 13th: 3.2km
Dan yr Ogof: show cave entrance to Great Hall Far North: 2.7km
Ogof Craig a Ffynnon: entrance to Promised Land: 2.1km
Little Neath River Cave: Bridge Cave to Sump 6B: 2.0km
Ogof Fynnon Ddu: Ogof y Nos Hir (OFD2 entrance) to Smiths Armoury: 1.4km

All the above distances err on the short side.

robjones said:

Scaling very roughly from surevys in Limestone and caves of Wales, other south Wales 'remote points' include:

Little Neath River Cave: Bridge Cave to Sump 6B: 2.0km

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Can't work it out precisely, 'cos my main comp is down, but from the start of that sump (6b is really sump 7) to the end of sump 8 will be another 400 m roughly.

No idea (I'd guess Draenen has the furthest in this country), but for a couple of northern caves, with very random guesses (i.e. look at survey, use fingers on length to very roughly measure the cave);
Langcliffe ~3km.
White Scar ~2.5km.
Birks Fell, Penyghent Pot and Cliff Force Cave must be at least 2km.
Such places as the end of Magnetometer, Mossdale or the d/s sump in the Fountains Fell Master Cave must be 1.5-2km.

Do mines get included, specifically those that intersect the natural, must be a few km to get to the far end of Devis these days?

And of course it depends if you are on about the nearest entrance to end (or most remote point), furthest entrance to end, does it include sumps (a couple of examples I mentioned above includes a sump or two on the way).

And of course, it's just numbers, if it's railway tunnel proportions then it's not that remote, throw in some challenging sections along the way and it can feel a lot longer and a damn site more remote!

The Milwr tunnel is 10miles from portal to forehead.

Chris.

ChrisJC said:

The Milwr tunnel is 10miles from portal to forehead.

Chris.

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But not actually that far from Cae Mawr...

I would guess for world would be somewhere in mammoth or lechuguilla or wind cave. America...bigger and better!

I have a feeling that when we helped Ulrich Meyer carry dive kit to the eastern end of the Hirlatz Hole in Austria years ago it was 12km from the entrance (2 & 1/2 days travelling each way), making it the most remote dive in Europe.  I'm also led to believe that the big caves in America all have multiple-entrances with cafes along the way so not sure just how remote their end points are. 

Amy said:

I would guess for world would be somewhere in mammoth or lechuguilla or wind cave. America...bigger and better!

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Definitely not Mammoth, which has entrances dotted all over the place.  Not very deep, either, we've got a dozen caves deeper than that on Mendip.

Was also going to go with Hirlatz in Austria. Now the end of that really is remote.

graham said:

Amy said:

I would guess for world would be somewhere in mammoth or lechuguilla or wind cave. America...bigger and better!

Click to expand...

Definitely not Mammoth, which has entrances dotted all over the place.  Not very deep, either, we've got a dozen caves deeper than that on Mendip.

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But lechuguilla has only one entrance....I would guess it is quite in the running.
I realize mammoth has many entrances but there are parts that do not...fisher ridge for example has I believe 3 entrances and is 120 miles of system not yet connected by passage to mammoth.

I'm going to chime in because I've been very curious about this stat and just happen to stumble on this topic.. Here's what I've heard from others (so it may not be perfectly accurate) as far as Tennessee Caves and how they compare to Mammoth: The furthest survey station in Roppel (which has the most distance place in the Mammoth Cave System) is somewhere around 6 miles (~9.7km) from an entrance. In Blue Spring Cave in Tennessee the furthest survey station from the entrance is around 6.5 miles (~10.4km); also Blue Spring has a 150ft (~46m) pit that's around 4.5 miles (~7.2km) from the entrance. In Rumbling Falls Cave in Tennessee the furthest station is around 5 miles (~8km) though, Rumbling Falls is surveyed in a "True Horizontal Distance" styled survey so, the actual distance would be longer than that. The path one must take to actually reach the end of Rumbling without having to boat down miles of river passage with very swift current is actually probably around 7 to 8 miles (~11km to 13km). Both Rumbling and Blue Spring don't necessarily end at their furthest points ether; Rumbling Falls in particular is viciously hard (physically demanding) to reach the end so, very few cavers have ever been there to push it further..  Fort Stanton Cave is well above all three of these in distance though; I just don't know how they have come up with their distance figure or very much about the cave at all for that matter...