Key takeaways
- The 670 is the double-deck railbus: a single-unit diesel railcar with two seating levels, built by DUEWAG in the 1990s.
- Fastest way to identify one: a single, short railcar with windows at two heights can hardly be anything else in Germany.
- Concept: the maximum number of seats over the minimum vehicle length for lightly used branch lines.
- No production success: the type stayed a tiny series; regional services opted for multi-part low-floor railcars instead.
- Historic today: anyone wanting to see the 670 researches museum settings, not the regular timetable.
Contents
Fact file
| Vehicle type | Single-unit diesel railcar in double-deck construction |
|---|---|
| Manufacturer | DUEWAG (Düsseldorfer Waggonfabrik) |
| Construction period | 1990s, tiny series with no successor type |
| UIC type code | 95 – diesel railcars |
| Distinguishing feature | Two seating levels in a single, short railcar |
| Current status | No longer in scheduled DB service; a few preserved units in museum settings |
Identifying features
Is this really the class in front of you?
- Single-unit railcar with two seating levels – virtually unique in Germany
- Low-set entrance area in the middle of the vehicle, seating areas above and below it
- Noticeably taller carbody than any other single-unit diesel railcar
- Short overall length despite the double-deck build – the proportions look squat
- Vehicle number begins with 670
- Window rows at two heights, one above the other, instead of a single continuous band
Updated: August 2026 – A single, short diesel railcar with windows on two levels: the Class 670 is one of the most unusual vehicles ever to run in German regional service. This page places the double-deck railbus in context, shows its recognition features, and explains how you can still find the few surviving vehicles at all.
Record rare vehicles
With types like the 670, every sighting is a one-off – document it with date, place and number and it stays verifiable.
What is the Class 670?
The Class 670 is a single-unit diesel railcar in double-deck construction, developed and built by DUEWAG in the 1990s. The manufacturer merged into Siemens Mobility shortly afterwards, where the concept found no continuation. It was an attempt to fit as many seats as possible into as short a vehicle as possible for lightly used branch lines – a vehicle meant to combine the economy of a railbus with the capacity of a double-deck coach.
The approach stayed a tiny series. In the same years, regional services opted for multi-part, low-floor railcars – the line represented by, for example, the Class 650 and the later articulated railcars. The 670 therefore remained a detour that’s mainly of interest today from a technical history point of view.
Why the body style is so unusual
Everyone knows double-deck vehicles from regional service – as long, locomotive-hauled trains or as multi-part multiple units. A single, short railcar with two seating levels, on the other hand, is a rarity.
The consequences are visible on every vehicle:
- The entrance area sits low in the middle of the vehicle, so that there’s room for two levels at all.
- Short stairs lead up and down from there into the seating areas.
- The windows therefore don’t sit in a single continuous band but in two staggered rows, one above the other.
- The carbody looks tall and squat overall, because the length is small and the height is large.
These very stairs are also the reason the concept didn’t catch on: they cost time during passenger changeover and work against step-free entry.
Historically, the 670 stands at the end of a long line of attempts to keep branch-line services economical. The basic question has been the same since the 1950s: how do you transport enough people on a lightly used line without running too large and too expensive a vehicle? The railbuses answered it with radical lightweight construction, the lightweight railcars of the Deutsche Reichsbahn with minimal vehicle size, modern articulated railcars with double-heading of short units. The 670 tried the third dimension – and failed not on capacity but on the demands for accessibility and passenger changeover that became ever more important in the 2000s.
For anyone studying rolling stock, that’s instructive: a technically sound solution can still fail in day-to-day operation. The type is therefore less a failure than a well-documented intermediate step.
How to identify the 670 in the field
Compare height and length
A vehicle that looks conspicuously tall for its length is the first clue. Normal single-unit railcars look flat and elongated.
Count the window rows
Two rows one above the other instead of a single continuous window band: this is the decisive feature and is visible from some distance already.
Look for the entrance
The entrance sits low and central. There are no doors at the vehicle ends here as on the classic railbus.
Confirm the number
The vehicle number begins with 670. Together with the full twelve-digit UIC number, the identification is unambiguous.
How to work through a chain of features like this systematically, instead of comparing details at random, is described in the guide to identifying locomotive classes.
Context in railway operations
The 670 clearly belongs to the historic fleet today. Scheduled deployment in regional service no longer takes place. That changes the search fundamentally: instead of the timetable and diagrams, event dates and owner information count.
| Search route | Chance of success | What you get there |
|---|---|---|
| Event pages of museum and heritage railways | medium | Firm information on planned workings |
| Specialist forums and sighting threads | medium | Current reports, often with a photo and date |
| Community sightings in apps | medium | Timely tips if others have already seen the vehicle |
| Older vehicle lists online | low | Often outdated – locations and owners change |
| DB’s regular timetable | none | No longer in scheduled service |
Don't take locations from old sources
Surviving individual vehicles change owner, storage location and operational status. What was true five years ago can be wrong today. If in doubt, ask the society or museum directly – it saves a wasted trip.
Use other spotters' sightings
Where a rare vehicle was last reported is often the most useful information there is.
Spotting and photo tips
The tall, short carbody of the 670 is a rewarding subject, because it immediately explains what’s going on. A pure front-on shot gives away exactly that.
A side view beats a front shot
The special feature of the class lies in the two window levels – and you only see that from the side or in a shallow three-quarter view. Plan your viewpoint so the whole side of the vehicle fits into the frame.
An interior shot is equally worthwhile, provided the vehicle is accessible and the operator has no objection: the two seating levels and the short stairs explain the concept immediately, while from the outside only the window arrangement gives it away.
How to find dates for special workings in the first place, without relying on rumours, is explained in the guide to special trains and special workings. For the world of heritage railways – research, contacts, typical procedures – the article on the heritage railway guide is worth reading.
House rules apply on museum grounds. Stick to designated paths and barriers, don’t enter track areas, and ask staff if in doubt. That’s not a formality: shunting happens on society grounds, often without the safety technology you know from large stations.
Common mix-ups
It points to the 670 if …
- a single, short railcar has two window levels
- the entrance sits low and central
- the vehicle looks conspicuously tall for its length
- the number starts with 670
Look more closely if …
- you only see the vehicle front-on or heavily foreshortened
- it's stabled between other vehicles
- it carries a special or society livery
It's not a 670 if …
- the vehicle consists of several carbody sections
- it has a single, continuous window band
- it's hauled by a locomotive – then it's a double-deck coach, not a railcar
The nearest comparison in regional service is the two-part Class 628 / 629: same job, same era, but a low body style and two carbody sections. From the East German branch-line tradition comes the Class 772 – also single-unit, but low and with a single row of windows.
Verdict
The Class 670 is a vehicle you only need to see once. Two window levels on a single, short diesel railcar don’t exist anywhere else in Germany. Operationally, the concept had no future because local services opted for low-floor, multi-part vehicles instead. For spotters, that’s exactly the appeal: whoever gets the 670 in front of a camera is documenting a dead end of vehicle development – and there’s no second one of those.
In short
Short, tall, two rows of windows: that's the 670. It no longer runs on a schedule, so the route runs via heritage railway event dates, specialist forums and current sighting reports – never via old location lists.
Archive historic vehicles properly
Record number, place, date and occasion – for rare types, that's half the research done for later.
Summary
- The Class 670 was a technical detour: double-deck, yet single-unit and short.
- The body style is so unusual that mixing it up with anything else is practically impossible.
- Regional services instead settled on low-floor articulated railcars – the 670 stayed an episode.
- Sightings are a matter of luck today and deserve especially careful documentation for that reason.
Frequently asked questions
What is the Class 670?
The Class 670 is a single-unit diesel railcar in double-deck construction, built by DUEWAG in the 1990s. It was meant to offer plenty of seats over a short vehicle length on lightly used branch lines. The type stayed a tiny series and found no successor in Germany.
Why is the 670 called the double-deck railbus?
Because it combines two concepts: the economy of the classic railbus for branch lines and the seating density of a double-deck coach. The name is a description, not an official designation – officially, only the class number 670 counts.
How do I recognise the Class 670?
By a feature that's rare anywhere else: window rows at two heights on a single, short railcar. The entrance sits low in the middle of the vehicle, with seating areas above and below it. Once you've seen this silhouette, you won't mix it up again.
Does the Class 670 still run in regular service?
No. Scheduled deployment in DB regional service no longer takes place. Surviving vehicles sit in museum or collector settings. Whether and when one of them runs is up to its owner – only up-to-date information can be relied on.
Why didn't the concept catch on?
Regional services in the 1990s and 2000s settled on low-floor, multi-part railcars with step-free entry. A double-deck vehicle inevitably brings stairs with it, which slows down passenger changeover and works against step-free access. Multi-part concepts solved the same capacity question more elegantly.
Where can I photograph the Class 670?
Realistically only at events, special workings or on museum grounds. The route there runs through the event pages of heritage and museum railways, specialist forums and community sightings. Never take fixed locations or dates from older sources – always check directly with the organiser.
What does type code 95 mean for this vehicle?
95 are the first two digits of the twelve-digit UIC vehicle number and stand for diesel railcars. The Class 670 therefore falls into the same type group as the classic railbuses and the modern regional railcars – regardless of how different the vehicles look.
Is the 670 related to a double-deck coach?
Only in concept, not in construction. Classic double-deck coaches are unpowered carriages hauled by a locomotive and are considerably longer. The 670 is a powered railcar that can run on its own – that's the decisive difference.
Log your sighting of the Class 670
Date, location and vehicle number logged in seconds – and visible to the community.
Related classes
Class 628 / 629
Class 628 is the classic two-part DB diesel railcar for regional services. The 629 is its twin-engined sister. Here's how to tell them apart in the field.
DMUClass 650 (Stadler Regio-Shuttle RS1)
The Regio-Shuttle RS1 of Class 650 is Germany's most distinctive single-part diesel railcar. Here's how to recognise it by its front, windows and roof.
DMUClass 772
The Class 772 is the Deutsche Reichsbahn's two-axle light railcar – known as the Ferkeltaxe and today found almost only at heritage railways.
DMUClass 7081
The Reihe 7081 is listed as a diesel railcar. Because reliable details are scarce, this page shows you the route via designation, number and design.
DMUVT 18.16
The VT 18.16 was the Deutsche Reichsbahn's express multiple unit: built in Görlitz, capable of 160 km/h, later Class 175. Today it's purely a museum vehicle.
DMUClass 1622 (Alstom Coradia LINT 54)
The Class 1622 is a two-car diesel railcar from Alstom's Coradia LINT family. Its four-digit number and type code 95 tell you a lot about the vehicle.
Who is behind it
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