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Where in London would gain from a mile long tunnel with stations at both ends?

The Pelican

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The DLR Thamesmead extension features a mile long, double track tunnel (in this case under the river) with a two platform station at either end. Where in London would you add a 1 mile tunnel with two end stations, assuming tunneling costs were equal everywhere?

I would propose a line with one end at Paddington, and the other end near the Royal Albert Hall, which would put it near the Northern end of the South Kensington Subway. Google's AI suggests that this distance is 1.1 Miles. It would improve access from the south western part of the circle line to the Elizabeth Line, and it could form the core of it's own tube line one day.
 
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cle

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Barking Riverside to Thamesmead /Abbey Wood instead possibly. Especially if it could enable through journeys, freight even.

Maybe a 1 mile spur from Kensal Green/Bakerloo to get into the heart of OOC. It has the frequency to enable it. Issue there is, it takes you to Paddington and onwards to West End when the EL does that far more directly, so would it be useful?

Or 1 mile of Central line from just before Ealing Broadway to West Ealing and then take over Greenford - two routes to West Ruislip. One could then go to Uxbridge as discussed a while back.

Battersea Power Station to Clapham Junction?
 

The Pelican

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Battersea Power Station to Clapham Junction?
There are quite a few interesting options from Battersea Power Station. Clapham Junction looks a bit beyond a mile, although less than two. South to rejoin or interchange with the existing Northern Line at Clapham North or Clapham Common would be an option, or north across the river to one of Victoria or Sloane Square, depending on whether the scheme design favours existing or new interchanges.
 

brad465

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Brixton-Herne Hill on the Victoria line, then shut Brixton mainline station. Provides Thameslink passengers a direct link to the Victoria line, speeds up Victoria-Orpington services (improving reliability for fast services following them) and reduces fare evasion through Brixton as a doughnut hotspot, as well as being unable to cope with the number of passengers changing to/from each line.
 

Howardh

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Does it have to be rail? A walking tunnel between Euston and St Pancras/King's Cross would be handy! But if it has to be rail I'd fill the gap between Tottenham Ct Rd and Picc Circus with a new station for Soho. It's about a mile (maybe less?) does that count?
 

The Pelican

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Does it have to be rail? A walking tunnel between Euston and St Pancras/King's Cross would be handy! But if it has to be rail I'd fill the gap between Tottenham Ct Rd and Picc Circus with a new station for Soho. It's about a mile (maybe less?) does that count?
The Chelsea Hackney Line, the automated metro version of Crossrail 2, and Crossrail 2 as it was most recently proposed all had versions of this- the first two by stopping at Piccadilly Circus and Tottenham Court Road, the latter by having a second entrance to it's Tottenham Court Road platforms on Shaftesbury Avenue.
Waterloo and City Line - Bank to Liverpool Street extension
Looks like a DLR extension from Bank to one of Farringdon or City Thameslink would be possible.

You could also build a second set of DLR tunnels parallel to the current ones, to two new DLR bank platforms, allowing everything which currently terminates at Tower Gateway to run to Bank.

Another good one would be Kingston to Surbiton- Kingston has a good service but no rail alternative if disrupted, which a fast link to Surbiton could provide (as long as the South Western main line wasn't disrupted too).
 
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cle

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How about from just north of Moorgate (on the northern City - with a new station there) to London Bridge and terminate it there.

It neeeearly gets you from Elephant to Camberwell Green on the Bakerloo.
 

The Pelican

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How about from just north of Moorgate (on the northern City - with a new station there) to London Bridge and terminate it there.
I have a feeling the Elizabeth line makes the Northern City difficult to extend, but a mile of tunnel might allow it to divert east of the Northern Line at Old Street, dive into a very deep Moorgate station east of the Northern Line and lower than the Elizabeth line, and continue to one more station at Bank, potentially with the Bank platforms called "Lothbury".
 

MarkyT

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Looks like a DLR extension from Bank to one of Farringdon or City Thameslink would be possible.

You could also build a second set of DLR tunnels parallel to the current ones, to two new DLR bank platforms, allowing everything which currently terminates at Tower Gateway to run to Bank.
I think the main constraint is the single reversing siding beyond the platforms at Bank through which all trains must run. An extension to a new terminus with two or more platforms might accommodate the full service, which fits on a single pair of tracks east of Tower Gateway.
 

The Pelican

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I think the main constraint is the single reversing siding beyond the platforms at Bank through which all trains must run. An extension to a new terminus with two or more platforms might accommodate the full service, which fits on a single pair of tracks east of Tower Gateway.
You could plan to eventually add two extra tracks (perhaps without platforms) through Shadwell, Limehouse and Westferry, so that the Bank-Westferry-Canary Wharf-Lewisham trains on one hand, and the Bank/Tower Gateway-Westferry-Poplar-Canning Town-Eastern Branches trains on the other, could each have their own tracks for substantial portions of the distance. This might allow a huge frequency increase in both groups, and the construction of an East London equivalent to the South Kensington-Acton corridor of the District and Piccaidlly lines. It might be better to put the fast lines in a tunnel!
 
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Waterloo to Kings Cross /St Pancras. Slightly longer than specified but it's daft there's no direct rail link between these two major stations.

Marylebone-Baker St, save the walk at street level to access the SSL, especially if you could add step free access to all platforms at Baker St at the same time.

Brixton-Streatham Hill (and ideally onto Streatham Station). The buses along this route are crazy busy, boarding a southbound bus at Brixton often resembles some kind of disaster movie!
 

Farigiraf

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City Airport to Custom House, links to the ExCeL and the Elizabeth line to access the city and Canary Wharf quicker. Currently requires a circuitous 1- or 2-transfer journey, a 5-minute taxi or a 30 minute walk that's nothing to write home about. Airport shuttles are common so it'd be a proven technology, plus you could probably get private financing. Let's not get into how you'd build it though :lol:

I second Baker Street to Marylebone, Euston HS1 to King's Cross and St Pancras could also do with a better link, though by the time you'd get on the monorail you're halfway there by foot so maybe the Crossrail 2 travellator would work better.

Liverpool Street - Fenchurch Street, possibly extending to London Bridge, is another chain of London terminals that could do with a better connection. In the theme of this thread, a 3-station shuttle train would do the job, although whether a gadgetbahn is the best solution for fixing some fairly annoying (if it's rainy, or if you have a tight connection, or if you have luggage) cross-London transfers is another discussion.
 

A S Leib

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Harrow and Wealdstone to Queensbury would be personally very convenient, although I imagine the BCR has many zeroes in it, if not negative.
I'm in almost exactly the same position in which a line from Harrow & Wealdstone to Kingsbury or (with better bus connections now) West Harrow would be appreciated, which isn't going to happen.
 

swt_passenger

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I don't know why people keep proposing extending the Waterloo and City at the Bank end. It’s been pointed out numerous times in previous speculative threads, eg by @Bald Rick, that:

”It’s simply not possible without closing other lines and demolishing some very expensive buildings to clear their basements.”
 

A S Leib

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I don't know why people keep proposing extending the Waterloo and City at the Bank end. It’s been pointed out numerous times in previous speculative threads, eg by @Bald Rick, that:

”It’s simply not possible without closing other lines and demolishing some very expensive buildings to clear their basements.”
Given the current W&C's a mile and a half, and the premise of this thread is a mile-long tunnel and two stations (unfortunately ruling out an interchange at Blackfriars), how deep could a second Waterloo & City line feasibly be built?
 

The Pelican

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The most interesting second Waterloo and City would take two tracks from either the SWML slows or the Windsor Lines (but not nessicarily everything on those two lines), have a two platform station serving Waterloo, then dive into a tunnel and have a two platform station serving Bank. It would be used as a kind of southern (Southern) version of each of:
1. The Great Northern and City
2.The St Pancras-Farringdon-Moorgate lines
3. Holborn Viaduct when in use as a terminal station.

(The difficulty in practise would be finding spare land for the two two platform stations)

Alternatively, such a tunnel could depart from the SWML tracks further west than Waterloo itself, but would probably struggle to find a terminal location as useful as it, or could head for the West End rather than the City, although the Victoria and Northern Line already do that.

(One of Crossrail 2's problems seemed to be that, although it served a London terminus on each side of London, it didn't serve the terminus that mainline trains go to for each of it's two surface branches- it did for the Alexandra Palace branch.)
 

Northumbriana

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I don't know why people keep proposing extending the Waterloo and City at the Bank end. It’s been pointed out numerous times in previous speculative threads, eg by @Bald Rick, that:

”It’s simply not possible without closing other lines and demolishing some very expensive buildings to clear their basements.”
Pedestrian level crossings in basements would be pretty interesting.
 

Bald Rick

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The most interesting second Waterloo and City would take two tracks from either the SWML slows or the Windsor Lines (but not nessicarily everything on those two lines), have a two platform station serving Waterloo, then dive into a tunnel and have a two platform station serving Bank. It would be used as a kind of southern (Southern) version of each of:
1. The Great Northern and City
2.The St Pancras-Farringdon-Moorgate lines
3. Holborn Viaduct when in use as a terminal station.

(The difficulty in practise would be finding spare land for the two two platform stations)

Alternatively, such a tunnel could depart from the SWML tracks further west than Waterloo itself, but would probably struggle to find a terminal location as useful as it, or could head for the West End rather than the City, although the Victoria and Northern Line already do that.

(One of Crossrail 2's problems seemed to be that, although it served a London terminus on each side of London, it didn't serve the terminus that mainline trains go to for each of it's two surface branches- it did for the Alexandra Palace branch.)

As Crossrail 2 found, the nearest to central London that a portal could feasibly be built is adjacent to Wandsworth cemetry.
 

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