Low mileage end / high mileage end?

[janeo]

Hi, I'm very new to rail and was wondering how the low mileage end and high mileage end are determined? Is it to do with the Up and the Down, e.g. the UP travels towards higher mileage and the Down towards lower mileage?

 

[lineclear]

Hi, I'm very new to rail and was wondering how the low mileage end and high mileage end are determined? Is it to do with the Up and the Down, e.g. the UP travels towards higher mileage and the Down towards lower mileage?

The mileage as displayed on mileposts increases in one direction; this is what 'high mileage' / 'low mileage' refers to. Usually, but not always, the Down direction is towards higher mileage.

 

[zwk500]

Welcome! Traditionally the down direction is travelling away from the 0 point (so mileage increases in the down direction). The 0 Datum point is traditionally the key station of the railway, such as the London Terminal. So GWR's lines count up from a 0 at Paddington, and the Midland Railway counted up from a 0 at St Pancras. A couple of non London 0 points are York (maybe only historically now), Glasgow, Manchester Victoria, Edinburgh.

Different railways had different policies, so branches might take 0 as the junction they left the main line, or they might keep counting all the way back from London. Also as railways got rebuilt and rerouted, various oddities appeared such as 'short' or 'long' miles, railways that started at negative mileages or railways that started at >0. Also as railways opened and closed lines, various gaps appeared. Occassionally a railway would carry out a big surveying exercise to get rid of some of these - the Midland did in the early 20th Century. However usually they'd just be left as they were. Also as early railways were built as separate concerns then linked together later, you can sometimes get mileages and zero points chopping and changing along a route.

The reason for the Down/Up nomeclature is that the early railways were required to produce strip maps showing key locations, these would be laid out with 0 at the top and then you read down the page. These documents have changed form many times, and now form what is called the Sectional Appendix, which is available from NR's website.

 

[Gloster]

There is a thread Up and Down (started 22 Nov 2020) on this forum which may supply some information (Sorry, I can’t do a link.)

 

[swt_passenger]

There is a thread Up and Down (started 22 Nov 2020) on this forum which may supply some information (Sorry, I can’t do a link.)

Here it is:

Up and Down

Raising as new thread, from this one on timetables, quoting posts from there, as a separately interesting one The 1850 Bradshaw (reprint unfortunately) has Tables headed 'Down' heading away from London (or any other route) alongside tables headed 'UP' in standard railway convention but the...

www.railforums.co.uk

 

[2192]

... Different railways had different policies, so branches might take 0 as the junction they left the main line, or they might keep counting all the way back from London. Also as railways got rebuilt and rerouted, various oddities appeared such as 'short' or 'long' miles, railways that started at negative mileages or railways that started at >0. Also as railways opened and closed lines, various gaps appeared. Occasionally a railway would carry out a big surveying exercise to get rid of some of these - the Midland did in the early 20th Century. However usually they'd just be left as they were....

Re-surveying and installing fresh mileposts cost a lot of money and as it didn't sell any more train tickets I am not surprised most railway companies didn't do it! Not doing it does lead to some oddities: the detour round the old Harecastle tunnel on the North Staffs line gives either a long mile of five quarters approx., or two different consecutive mileposts bearing the same number of miles.

 

[zwk500]

Re-surveying and installing fresh mileposts cost a lot of money and as it didn't sell any more train tickets I am not surprised most railway companies didn't do it! Not doing it does lead to some oddities: the detour round the old Harecastle tunnel on the North Staffs line gives either a long mile of five quarters approx., or two different consecutive mileposts bearing the same number of miles.

Indeed! The interesting thing for me is that Short/Long miles have never been noted as such in the Sectional appendix, so if you don't know they're there you miss them completely, whereas 'proper' changes of mileage (i.e. changes of the 0 datum) are noted in NESA.

Presumably recalculating did have some advantages, or the Midland wouldn't have bothered. I'd guess it made calculating operating and maintenance costs easier as there weren't random changes of mileage everywhere. Possibly also had commercial applications like calculating fares to/from London being easier as everybody had the 'official' distance. Of course, nowadays with fare not linked to distance there's even less advantages to resurveying the lot.

 

[randyrippley]

Then you have the historic oddity of the WCML resetting to 0 at Preston, Lancaster and Carlisle

those don't need a re-survey, just needs someone to do some sums

 

[zwk500]

Then you have the historic oddity of the WCML resetting to 0 at Preston, Lancaster and Carlisle

those don't need a re-survey, just needs someone to do some sums

Tbh, given the frequency of 'odd miles' on the WCML, if you're doing a remilage you may as well do it properly.

 

[LNW-GW Joint]

Then you have the historic oddity of the WCML resetting to 0 at Preston, Lancaster and Carlisle
those don't need a re-survey, just needs someone to do some sums

And at Golborne Jn (from 0 at Newton le Willows Jn on the L&M).

Marylebone is the one London terminus without a zero.
Mileage (MS&L/GC) starts at Manchester London Road via Woodhead, Sheffield and Aylesbury: Marylebone buffer stops are at 205m77c.

 

[edwin_m]

Re-surveying and installing fresh mileposts cost a lot of money and as it didn't sell any more train tickets I am not surprised most railway companies didn't do it! Not doing it does lead to some oddities: the detour round the old Harecastle tunnel on the North Staffs line gives either a long mile of five quarters approx., or two different consecutive mileposts bearing the same number of miles.

It would also cause a lot of confusion for the engineers, considering how many locations and pieces of equipment are referenced to Engineers' Line Reference and mileage. Wherever there is a long mile the ELR should be changing, at least the final digit, so that the combination of ELR and mileage gives a unique position on the network. This appears to be the case at Harecastle (per an oldish Quail map), where the ELR changes from CMD2 milepost 16 to CMD1 15 miles 65 chains going southwards (direction of increasing mileage being "up" on this route). There is also a CMD3 for the abandoned route through the tunnel which may still have assets that need to be maintained.

 

[janeo]

The mileage as displayed on mileposts increases in one direction; this is what 'high mileage' / 'low mileage' refers to. Usually, but not always, the Down direction is towards higher mileage.

Thanks to everyone for their replies - much appreciated, its a darker magic than I at first thought!

 

[flitwickbeds]

What happens in the Thameslink core, both for the core build itself and the newer connection to the ECML?

Presumably St Pancras is zero for the Midland Mainline, do the numbers go into minus until, say, London Bridge where it resets to zero again?

 

[LNW-GW Joint]

What happens in the Thameslink core, both for the core build itself and the newer connection to the ECML?
Presumably St Pancras is zero for the Midland Mainline, do the numbers go into minus until, say, London Bridge where it resets to zero again?

There is a separate zero for the Midland City Line at Moorgate via St Pancras (Thameslink) and Kentish Town, terminating at Carlton Road Jn (4.06 from Moorgate, 2.17 from St Pancras CTRL buffers.
Today this covers the route north from Farringdon Jn which is at 0.58 from Moorgate, with St Pancras (Thameslink) being at 2.11.

Towards the south, mileages were measured from a zero at the old Holborn Viaduct station towards Tulse Hill, with Blackfriars station being at 0.30.
The Farringdon-Blackfriars section through Snow Hill tunnel has its own sequence, from zero at Farringdon Jn until the merging of the two routes near Blackfriars (0.39 from Farrington, 0.21 from Holborn Viaduct).
The link from St Pancras Thameslink to the ECML has its own mileage run from zero at Canal Tunnel Jn (2.25 on the Moorgate mileage) to 0.53 at Belle Isle Jn on the ECML (which is 0.57 from the King's Cross buffers).

It's one of the most complex sections of the NR network, and has always been a borderland between the old companies, BR's regions and (today) NR's routes.
It's all detailed in the Quail (Trackmaps) maps, but you need three volumes (Midlands & NW, Southern & TfL and Eastern) to cover the few miles of railway involved.
Some of the detail may have changed in recent remodelling and realignment works, most recently near King's Cross.

 

[Annetts key]

Thanks to everyone for their replies - much appreciated, its a darker magic than I at first thought!

As you have noticed, it’s very complex. Just like a lot of things to do with the railways…

Some lines have different (multiple) engineers line references (ELR) even in between junctions (because what exists today is a combination of parts of multiple routes that were part of a larger railway network), some of which have different mileage start points (which may no longer exist) and in the past what was the up line and what was the down lines changed over.

In my area, that means the mile and quarter mile posts are sometimes on the downside rather than on the upside (which is the normal convention).

To sum up, I think this saying is appropriate: there’s the right way, the wrong way and the railway!

 

[swt_passenger]

There is a separate zero for the Midland City Line at Moorgate via St Pancras (Thameslink) and Kentish Town, terminating at Carlton Road Jn (4.06 from Moorgate, 2.17 from St Pancras CTRL buffers.
Today this covers the route north from Farringdon Jn which is at 0.58 from Moorgate, with St Pancras (Thameslink) being at 2.11.
[…]
Some of the detail may have changed in recent remodelling and realignment works, most recently near King's Cross.

The LNER online sectional appendix (SA) has the line names slightly different around Farringdon now, they match the route boundary change made a few years ago, as that’s now just off the north end of Farringdon platforms at 66ch. Farringdon station is still at 62ch though. So the lines through the platforms are now up/down Snow Hill, with up/down Moorgate starting at the 66ch point.

Presumably this was to do with the removal of Farringdon Junction which is no longer mentioned in either of the relevant SAs. Or put another way, the change of mileage is at the same place, but it’s no longer got a name?

 

[miklcct]

The mileage as displayed on mileposts increases in one direction; this is what 'high mileage' / 'low mileage' refers to. Usually, but not always, the Down direction is towards higher mileage.

I always find it confusing when the track direction is the opposite to the mileage direction - i.e. the mileage goes up following the down direction.

In everyday conversation, positive numbers are always associated with the up direction, both in buildings and in elevations.

 

[Bevan Price]

Then you have the historic oddity of the WCML resetting to 0 at Preston, Lancaster and Carlisle

those don't need a re-survey, just needs someone to do some sums

That is down to railway construction history - the zero points were those chosen by separate railway companies, which only later became part of LNWR then LMSR.