Stuttgart 21 becomes Stuttgart 31

[CdBrux]

Not sure I have seen this mentioned on the forums so far. Up until a few weeks ago this was, publically at least, due to start opening from December this year (2026)

https://www.swr.de/swraktuell/baden-wuerttemberg/stuttgart/s21-bahn-falsche-kabel-ects-100.html

In an attempt to meet the opening date for the Stuttgart 21 project, the railway company hastily laid the wrong cables – and now cannot put the station into operation until 2031. There are also other reasons for the delay.

To say this has gone down quite badly is an understatement!

 

[Sir Felix Pole]

Ah, but it has been rebranded as Stuttgart 21st Century so all good and plenty of scope for further delay. Seriously, one wonders whether it would have been better to construct an temporary station somewhere on the avoiding line to the north of city for main-line trains (and connected to the city by the Stadbahn) rather than trying to work around rebuilding of the Hbf.

 

[The exile]

Ah, but it has been rebranded as Stuttgart 21st Century so all good and plenty of scope for further delay. Seriously, one wonders whether it would have been better to construct an temporary station somewhere on the avoiding line to the north of city for main-line trains (and connected to the city by the Stadbahn) rather than trying to work around rebuilding of the Hbf.

Isn’t hindsight a wonderful thing.

 

[CdBrux]

Not sure the delays are really caused by rebuilding Hbf, more just general problems. The latest, as I understand, comes mainly from choosing the wrong type of signalling system and now having to rip out what has already been installed!

 

[U-Bahnfreund]

There are multiple factors, as explained in this slideshow from the S21 meeting on 26 June: https://www.bahnprojekt-stuttgart-u...sentation-Lenkungskreis-Stuttgart-21-data.pdf

1) in 2020, it was decided to build Stuttgart 21 as a landmark first-of-a-kind digital signalling system, ETCS Level 2 w/o signals and ATO. Since this has never been installed before in Germany, a lot of technical and software components have to be developed new. Hitachi, DB and responsible authority examiners apparently have all missed deadlines
2) because DB didn't want to miss the opening deadline again, they started laying cable channels and cables that they thought would be needed, and only later received the actual specifications from Hitachi. Not all, but some low three-digit km length of cables need to be replaced apparently
3) the technical equipment building from 2013 isn't fit for purpose anymore since a lot of specifications have changed
4) rules around redundancy in emergency power system have changed. It's now inevitable that the whole system needs to be rebuilt, because the newer regulations require more redundancy

The new timeline for opening is now this:
- December 2027: station building reopens so footpaths to/from the platforms can be shortened by a lot
- December 2028: station building fully finished with shops and other amenities
- December 2030: Stuttgart Airport station opens with regional services from Ulm and Tübingen
- December 2031: underground through stations opens, first the axis from Karlsruhe/Mannheim to the airport and Esslingen
- March 2032: Gäubahn from Zürich cut short at Stuttgart-Vaihingen station, doesn't serve Stuttgart Hbf anymore
- July 2032: extended S-Bahn trunk route with new Rosenstein/Mittnachtstraße station opens
- July 2032: aboveground station closes, as tunnel route to/from Bad Cannstatt is opened and regional trains from Aalen/Crailsheim/Schwäbisch Hall can be diverted into the new station
- December 2033: new Böblingen-Airport tunnel opens, Gäubahn trains can be diverted to Stuttgart Hbf

 

[Nicholas Lewis]

There are multiple factors, as explained in this slideshow from the S21 meeting on 26 June: https://www.bahnprojekt-stuttgart-u...sentation-Lenkungskreis-Stuttgart-21-data.pdf

1) in 2020, it was decided to build Stuttgart 21 as a landmark first-of-a-kind digital signalling system, ETCS Level 2 w/o signals and ATO. Since this has never been installed before in Germany, a lot of technical and software components have to be developed new. Hitachi, DB and responsible authority examiners apparently have all missed deadlines
2) because DB didn't want to miss the opening deadline again, they started laying cable channels and cables that they thought would be needed, and only later received the actual specifications from Hitachi. Not all, but some low three-digit km length of cables need to be replaced apparently
3) the technical equipment building from 2013 isn't fit for purpose anymore since a lot of specifications have changed
4) rules around redundancy in emergency power system have changed. It's now inevitable that the whole system needs to be rebuilt, because the newer regulations require more redundancy

The new timeline for opening is now this:
- December 2027: station building reopens so footpaths to/from the platforms can be shortened by a lot
- December 2028: station building fully finished with shops and other amenities
- December 2030: Stuttgart Airport station opens with regional services from Ulm and Tübingen
- December 2031: underground through stations opens, first the axis from Karlsruhe/Mannheim to the airport and Esslingen
- March 2032: Gäubahn from Zürich cut short at Stuttgart-Vaihingen station, doesn't serve Stuttgart Hbf anymore
- July 2032: extended S-Bahn trunk route with new Rosenstein/Mittnachtstraße station opens
- July 2032: aboveground station closes, as tunnel route to/from Bad Cannstatt is opened and regional trains from Aalen/Crailsheim/Schwäbisch Hall can be diverted into the new station
- December 2033: new Böblingen-Airport tunnel opens, Gäubahn trains can be diverted to Stuttgart Hbf

The debacle here and previously at Brandenburg airport make the UKs Crossrail and HS2 woes reasonably modest. Although across all of them they get within striking distance of compeltion when you judge them on the physical state yet then a bombshell like this lands. To my mind we are over complicating the systems that run these infrastructure projects and finding them unmanageable when it comes to integration. Time to consult the Chinese on best practice!

 

[Stossgebet]

The debacle here and previously at Brandenburg airport make the UKs Crossrail and HS2 woes reasonably modest. Although across all of them they get within striking distance of compeltion when you judge them on the physical state yet then a bombshell like this lands. To my mind we are over complicating the systems that run these infrastructure projects and finding them unmanageable when it comes to integration. Time to consult the Chinese on best practice!

Yes.
The idea of building long term construction projects and with long building durations, really does make the idea of changing standards during the building phase look very questionable.
It really is a chicken and egg situation!

Though my concern is will the new through station be big enough? How long ago was this project designed (decades?), and does the new station have room to accomodate much extra passenger growth, or have they designed it with a future capacity crunch by accident?

 

[The exile]

The debacle here and previously at Brandenburg airport make the UKs Crossrail and HS2 woes reasonably modest. Although across all of them they get within striking distance of compeltion when you judge them on the physical state yet then a bombshell like this lands. To my mind we are over complicating the systems that run these infrastructure projects and finding them unmanageable when it comes to integration. Time to consult the Chinese on best practice!

Add in the sorry tale of the collapsing U-Bahn tunnel under Cologne - on entirely a different scale to Gerard’s Cross or the Heathrow Tunnel.

 

[stuu]

Yes the Cologne thing is extraordinary. It will have taken 20 years between the collapse and the line opening. Just checked online, the opening date is now 2032. Perhaps they have the same builders as HS2?

 

[The exile]

Yes the Cologne thing is extraordinary. It will have taken 20 years between the collapse and the line opening. Just checked online, the opening date is now 2032. Perhaps they have the same builders as HS2?

Guessing they had to finish the inquiry and criminal investigation before reletting contracts and effectively starting from scratch but with a whole lot of half-completed potentially dangerous “workmanship” in the way.

 

[Austriantrain]

Though my concern is will the new through station be big enough? How long ago was this project designed (decades?), and does the new station have room to accomodate much extra passenger growth, or have they designed it with a future capacity crunch by accident?

Many people have the same concerns. And I still don’t believe Stuttgart 21 ever was a good project (except for the land redevelopers when the old station is gone; obviously parts of the proceeds will go towards the station), especially with the hugely increased price tag. How much other stuff you could have built to increase capacity in the Stuttgart region and achieve the same or better time savings there and elsewhere with the money spent…

 

[CdBrux]

As someone who occasionally travels from Munich to Mannheim or Karlsruhe I was looking forward to shortening journey times by a good 15 mins!
More importantly I agree this looks to be an illustrations of the risk of scope change half way through, and/or agreeing to use new technologies that are not yet proven ready. Had they chosen existing technologies yes it might be on the verge of being not the latest when opening but would have the advantage of a major de-risk (and actually opening closer to on time and thus before the technology became outdated!).
I wonder to what extent HS2 has done the same thing in some aspects. Stick with what you know is more boring but often more than good enough!

== Doublepost prevention - post automatically merged: 1 Jul 2026 ==

Many people have the same concerns. And I still don’t believe Stuttgart 21 ever was a good project (except for the land redevelopers when the old station is gone; obviously parts of the proceeds will go towards the station), especially with the hugely increased price tag. How much other stuff you could have built to increase capacity in the Stuttgart region and achieve the same or better time savings there and elsewhere with the money spent…

message to Mr Burnham re: underground Piccadilly for NPR / HS2 !!

 

[The exile]

I wonder how much this is an example of a “generally good idea” becoming a blinkered ideology? Referring to the “terminus bad; through station good” which makes a lot of sense under certain circumstances:

1. You’re starting from scratch (or near scratch as in the post war reconstructions at Braunschweig and Heidelberg)

2. The through line allows you to bring local services nearer to city centres (the S-Bahn tunnels in Frankfurt, Munich and Stuttgart itself)

3. Reversals involve complicated loco changes

4. There’s a lot of railway land that can be released.

At the time this project was conceived 3 and 4 probably applied. 3 has been largely rendered moot and 4 is apparently not likely to be realised as much as originally intended (IIRC). Was it worth it? Time will tell - as it will for the replacement of HH-Altona, about which I also have my doubts.

 

[Austriantrain]

I wonder how much this is an example of a “generally good idea” becoming a blinkered ideology? Referring to the “terminus bad; through station good” which makes a lot of sense under certain circumstances

Like in most areas of life, ideology should be left at the door of rail policy. I don’t believe in „terminus bad, through station good“ or vice versa as an absolute rule. It depends on topography, route geography, planned timetable and much, much more.

I am not German and don’t pay my taxes there, but I never found the case for S21 quite convincing. OTOH, the plans for an underground through long-distance station at Frankfurt Hbf I can perfectly understand.

And as Wien Hbf shows: if you build a through station, better plan for growth or you will come to regret it.

 

[The Pelican]

Stuttgart always seems to have grown especially quickly in the 20th century- Google suggests is had 177,000 people in 1900, vs 500,000 in Munich and 1,900,000 in Berlin! That means that it's a very generously layed out city, with lots of green space near the centre. I think the through tunnel was a good idea, but would have rotated it roughly 90 degrees and given it a second, "City Center", station.

It should also have a high speed line to Freiburg, which should be fast enough to be faster than the Rhein Valley route between Freiburg and Frankfurt. That, plus the existing Paris-Munich route, would really put it at the crossroads of Europe!

(On the other hand, I think it has the best tram system in the world.)

 

[A S Leib]

On the other hand, I think it has the best tram system in the world.

The exits at Charlottenplatz and directions there and at Schlossplatz have confused me each time I've used them; otherwise, I quite like it, and how frequent the S-Bahn is (up to 24 tph in the core, compared to 5 or 6 for Rhein-Neckar's interpretation of an S-Bahn).

 

[The Pelican]

I think the great thing about tram system is that it keeps popping above ground and underground, and has almost every sort of tram line in different places- reserved, street running, mixed traffic etc. The Filder hill, climbed by one cogwheel railway, one tube-style tunnel, and one old-fashioned hill climbing tramway is particularly impressive- it lets you see several different ways to climb a hill next to each other.

 

[fandroid]

I've been travelling through Stuttgart regularly for the last 15 years and, in theory at least, Stuttgart 21 would have made my journeys a lot easier and quicker, as many of those trips involved flying in to the airport and travelling on to Ulm, Tubingen and Stuttgart city centre. Like most here I can look back to the old uncluttered Hbf with nostalgia. As it is, even the newish tunneled high-speed line from Ulm stops short and any time gain is destroyed by the need to divert back onto the old main line.

So, until I retire in the next year or so, it will still be the bus as first choice for Tubingen and the slowish and not very frequent old S-bahn route into the city.

I too am impressed by the Stadtbahn. My only gripe is the apparent absence of any Network maps at all in the bewildering interchange station under the platz by the Hbf.

 

[The Pelican]

An interesting comparison with a more simple through tracks project- LA's "Link Union Station" running through tracks south of LA Union Station's former terminus platforms- suggests that the LA project is costing about $3 Billion and the Stuttgart project about €18 Billion.

Stuttgart seem to be getting a lot more for their money though, with tunelled approaches for a considerable distance.

When comparing American and European transport projects, it's useful to also consider train operating techniques- LA Union station seems to be operated in a way where all the suburban trains arrive and leave at the same time. Broadly, LA's project is for outer suburban trains, and Stuttgart's is for reigonal ones- the suburban trains already use the S bahn tunnel.

All useful food for thought for any Manchester Piccadilly through services, whether reversing in overground HS2 terminus platforms or running through a tunnel.

 

[fandroid]

Stuttgart's project covers almost the whole spectrum of rail passenger transport, local, regional, national and international. One of the drivers seems to be the European corridor connecting Paris to Budapest via Stuttgart, Munich and Vienna. I think!

 

[NCT]

My understanding is that Stuttgart 21 has always been a land-release project and not a transport need driven project. Stuttgart is hemmed in by hills and is in desperate need of additional land for housing. As a result there's a lot of vanity in it and poorly thought out technical aspects. Platforms are on a gradient non-compliant for splitting/joining operations; the track layout is asymmetrical. Even as a land released the project needn't have taken the shape it has taken.

The best way to reduce terminus platform requirement is not to remove intercity services but to remove regional ones. This way your cross city tunnel and station(s) only need to be Thameslink sized - with 250-metre rather than 400-metre platforms.

Intercity services just need to be separated into terminating and bypassing. If Manchester and Birmingham are big enough for this model so is Stuttgart. Yes, you'd still need a terminus station but it only need be half its current size, and much of the existing land take isn't from the station itself but the yard behind it, the removal of which doesn't depend on having an underground through station. An intercity bypass line would have cost a small fraction of the behemoth that's currently being built.

The same argument applies for Frankfurt. It's not intercity services that should be sent underground, but regional ones.

 

[The exile]

My understanding is that Stuttgart 21 has always been a land-release project and not a transport need driven project. Stuttgart is hemmed in by hills and is in desperate need of additional land for housing. As a result there's a lot of vanity in it and poorly thought out technical aspects. Platforms are on a gradient non-compliant for splitting/joining operations; the track layout is asymmetrical. Even as a land released the project needn't have taken the shape it has taken.

The best way to reduce terminus platform requirement is not to remove intercity services but to remove regional ones. This way your cross city tunnel and station(s) only need to be Thameslink sized - with 250-metre rather than 400-metre platforms.

Intercity services just need to be separated into terminating and bypassing. If Manchester and Birmingham are big enough for this model so is Stuttgart. Yes, you'd still need a terminus station but it only need be half its current size, and much of the existing land take isn't from the station itself but the yard behind it, the removal of which doesn't depend on having an underground through station. An intercity bypass line would have cost a small fraction of the behemoth that's currently being built.

The same argument applies for Frankfurt. It's not intercity services that should be sent underground, but regional ones.

As well as the land-release element, this project dates so far back that one of the elements will have been the desire to eliminate loco-changes and reversals based on the pre-ICE notion that inter city trains and push-pull don’t go together. The other “elephants” on the room are the need to improve routes to the Southwest (the Gaubahn) and, more importantly in the eyes of politicians, maintaining as many connections as possible to the state capital. (Compare the various battles that poor old Wiesbaden has had). More practically, maintaining the interchange facility, which would have been degraded by an ICE station at Zazenhausen or similar.
Remains to be seen whether it’ll have been worth it in the end.

 

[Austriantrain]

As well as the land-release element, this project dates so far back that one of the elements will have been the desire to eliminate loco-changes and reversals based on the pre-ICE notion that inter city trains and push-pull don’t go together. The other “elephants” on the room are the need to improve routes to the Southwest (the Gaubahn) and, more importantly in the eyes of politicians, maintaining as many connections as possible to the state capital. (Compare the various battles that poor old Wiesbaden has had). More practically, maintaining the interchange facility, which would have been degraded by an ICE station at Zazenhausen or similar.
Remains to be seen whether it’ll have been worth it in the end.

There would have been nothing inherently wrong with just keeping the terminus and improving access. Time loss would have been negligible and easily compensated elsewhere. Probably much to NCT‘s surprise , I am not a through station freak (same thing BTW for Florence - through roads for nonstop trains yes, a new station for stopping trains - not useful in my opinion).

I am not sure if the station has enough platform capacity, but while above ground there does not some space for more, a much cheaper underground terminal under the Schlossgarten does appear possible.

 

[ac6000cw]

An interesting comparison with a more simple through tracks project- LA's "Link Union Station" running through tracks south of LA Union Station's former terminus platforms- suggests that the LA project is costing about $3 Billion and the Stuttgart project about €18 Billion.

Stuttgart seem to be getting a lot more for their money though, with tunelled approaches for a considerable distance.

When comparing American and European transport projects, it's useful to also consider train operating techniques- LA Union station seems to be operated in a way where all the suburban trains arrive and leave at the same time. Broadly, LA's project is for outer suburban trains, and Stuttgart's is for reigonal ones- the suburban trains already use the S bahn tunnel.

All useful food for thought for any Manchester Piccadilly through services, whether reversing in overground HS2 terminus platforms or running through a tunnel.

The LA Union Station "Link Union Station" project is also made easier because LAUS was originally designed (in the late 1930s) to allow for possible conversion into a through station in the future - its general layout is like a through station, but with bumping posts (US equivalent of buffer stops) at the south end of the platform tracks - https://maps.app.goo.gl/aXLDYVPUvT7gycGR6

 

[NCT]

As well as the land-release element, this project dates so far back that one of the elements will have been the desire to eliminate loco-changes and reversals based on the pre-ICE notion that inter city trains and push-pull don’t go together. The other “elephants” on the room are the need to improve routes to the Southwest (the Gaubahn) and, more importantly in the eyes of politicians, maintaining as many connections as possible to the state capital. (Compare the various battles that poor old Wiesbaden has had). More practically, maintaining the interchange facility, which would have been degraded by an ICE station at Zazenhausen or similar.
Remains to be seen whether it’ll have been worth it in the end.

The Gaubahn element is most definitely political vanity. As for Wiesbaden, at some point Ze Germans will have to accept it's a Frankfurt suburb.

There would have been nothing inherently wrong with just keeping the terminus and improving access. Time loss would have been negligible and easily compensated elsewhere. Probably much to NCT‘s surprise , I am not a through station freak (same thing BTW for Florence - through roads for nonstop trains yes, a new station for stopping trains - not useful in my opinion).

I am not sure if the station has enough platform capacity, but while above ground there does not some space for more, a much cheaper underground terminal under the Schlossgarten does appear possible.

Florence is a tricky one. Belfiore makes high-speed trains remote from other trains and the station itself isn't well located. There are currently (in a stylised way) 4tph not stopping at Florence and up to 6tph that do stop/reverse at Florence, and I think this ratio is about right long-term. If infrastructure is needed, it becomes a question of whether you build new infrastructure for majority or minority traffic. With 6tph doing Milan - Rome it's logical to have via Florence and not via Florence services; the Venice and Verona runs (at 2tph and 1tph respectively) can't easily be separated. Having 6tph reversing and Venice - Rome passengers suffering the journey time penalty as a long-term end state isn't ideal. I'm not sure what the best solution is. At least Belfjore isn't the clusterfvck that Stuttgart 31 is.

 

[The exile]

The Gaubahn element is most definitely political vanity. As for Wiesbaden, at some point Ze Germans will have to accept it's a Frankfurt suburb.

That (although the local powers that be would never admit it) is probably what kept the political pressure relatively low and only spawned the Wiesbaden City and a couple of NBS curves….

 

[stuu]

At least Belfjore isn't the clusterfvck that Stuttgart 31 is.

Apart from the fact it will have taken nearly 25 years to build it, assuming it opens on time

 

[Austriantrain]

Florence is a tricky one. Belfiore makes high-speed trains remote from other trains and the station itself isn't well located. There are currently (in a stylised way) 4tph not stopping at Florence and up to 6tph that do stop/reverse at Florence, and I think this ratio is about right long-term. If infrastructure is needed, it becomes a question of whether you build new infrastructure for majority or minority traffic. With 6tph doing Milan - Rome it's logical to have via Florence and not via Florence services; the Venice and Verona runs (at 2tph and 1tph respectively) can't easily be separated. Having 6tph reversing and Venice - Rome passengers suffering the journey time penalty as a long-term end state isn't ideal. I'm not sure what the best solution is. At least Belfjore isn't the clusterfvck that Stuttgart 31 is.

My personal preference in cases like this one is always the same: never disconnect an important service from the main hub, unless you can provide a comparable alternative, which Belfiore isn’t. If capacity in the S.M.N approaches dictates that through trains need separate through tracks, then that might be argued even for just 4 tph (in each direction). If capacity is not an issue, it depends on how much money a time saving of 5-10 minutes is worth the Italian taxpayer - not going to judge here.

 

[NCT]

Apart from the fact it will have taken nearly 25 years to build it, assuming it opens on time

Every time I learn something new about project delivery in another European country I feel a bit better about Britain.

 

[The exile]

Every time I learn something new about project delivery in another European country I feel a bit better about Britain.

It’s something that is worth remembering across the board. These big project “problems” are relatively easy to find out about. Far less so at the “daily annoyance” level where we’re confronted with our own deficiencies (and there’s plenty of them) but it’s not so easy to realise that the grass isn’t always greener elsewhere. Sometimes it is, of course, and we shouldn’t be complacent, but the usual riposte to “This wouldn’t happen in (insert country)” is “Oh yes, it would!”