Key takeaways
- The VT 10 is a historic diesel railcar of the GKB and is carried under Class 5010.
- The leading 5 of the class number marks a diesel multiple unit in the Austrian scheme – this applies outside the ÖBB too.
- The full number 9581 5010 002-1 A-GKB can be read block by block and reveals type, country, class and keeper.
- Railbuses are light railcars: economical, nimble and originally intended for lightly used branch lines.
- Encounters can be planned but aren't everyday – they depend on special-trip dates, not the regular timetable.
Contents
Fact file
| Vehicle type | Diesel railcar of railbus design |
|---|---|
| Keeper | Graz-Köflacher Bahn (GKB), keeper marking A-GKB |
| Designation system | Class 5010 – the leading 5 in the Austrian scheme stands for diesel multiple units |
| Running number | 9581 5010 002-1 A-GKB |
| Country code | 81 – Austria |
| Status | Historic vehicle, used mainly for special and heritage trips |
| Traction | Combustion engine on board, no overhead line required |
Identifying features
Is this really the class in front of you?
- Lightweight railcar of railbus design borrowing from road-vehicle construction
- No pantograph on the roof – the traction unit sits on board
- Vehicle marking 9581 5010 002-1 A-GKB instead of an ÖBB keeper code
- Historic styling, clearly set apart from current regional railcars
- Typically appears at special trips, not in dense scheduled service
- Keeper marking GKB points to a private railway, not the state railway
Updated: August 2026 – A small railcar with borrowings from bus construction, no pantograph, marked 9581 5010 002-1 A-GKB: the VT 10 of the Graz-Köflacher Bahn is a historic vehicle and, at the same time, one of the best opportunities to learn the Austrian numbering system through a concrete example. This page explains both.
Spotted a historic vehicle?
Special trips don't repeat. Record the date, occasion and vehicle number while you're still on site.
What is the GKB VT 10 of Class 5010?
The VT 10 is a diesel railcar of railbus design belonging to the Graz-Köflacher Bahn, carried under Class 5010. Railbuses are light railcars: they adopt design principles from road-vehicle construction to cut weight, fuel use and operating costs. They were developed for branch lines where a full train with a locomotive would simply have been too costly.
Two things make this vehicle interesting for spotters. First, it’s a private-railway vehicle – the GKB is an independent railway company and not part of the ÖBB, much like the Stern & Hafferl Verkehrsgesellschaft in Upper Austria. Second, it’s a historic vehicle that doesn’t run in the regular timetable but is deployed at announced special trips. Both properties appear directly in the vehicle’s marking.
The vehicle number decoded
Every rail vehicle in Europe carries a twelve-digit number. For the VT 10 it reads 9581 5010 002-1 and is supplemented by the keeper marking A-GKB. Read block by block, it produces a complete profile.
| Block | Value | Meaning |
|---|---|---|
| Type code | 95 | Identifies the vehicle type within the system |
| Country code | 81 | Austria – for German vehicles this would read 80 |
| Class | 5010 | Leading 5 = diesel railcar in the Austrian scheme |
| Running number | 002 | Sequential number within the class |
| Check digit | 1 | Arithmetic safeguard against transposed digits |
| Keeper marking | A-GKB | A = Austria, GKB = Graz-Köflacher Bahn |
This system is the real value of this page: it works for every Austrian vehicle. The leading digit of the four-digit class always reveals the vehicle type – 1 for electric locomotives, 2 for diesel locomotives, 4 for electric railcars, 5 for diesel railcars, 6 for driving trailers, 7 for trailer cars. How the whole numbering system is structured and where the markings sit on the vehicle is covered in more depth in the guide to the ÖBB number and UIC wagon number.
How to recognise a railbus in the field
Step 1: scan the roof
No pantograph means the traction unit must sit on board. That rules out every electric class straight away.
Step 2: judge the size
Railbuses look noticeably smaller and lighter than today's regional railcars. The car body is low and narrowly proportioned.
Step 3: read the styling
Angular surfaces, small windows, visible rivets or beading instead of smoothly bonded glazing – that's the signature of older vehicle generations.
Step 4: check the keeper marking
If A-GKB appears on the side of the car, the keeper is unambiguous – and so is the fact that you're not looking at an ÖBB vehicle.
Don't miss special trips
Community reports show you when historic vehicles are out and about – in good time before the date.
What a historic vehicle means for planning
For vehicles in regular service, location decides success. For historic vehicles, the date decides it. That turns the whole planning process around.
- Date first, then location. A special trip happens on one day. Only once that’s fixed is it worth looking for a suitable spot along the route.
- Announcements are the primary source. Operators and societies announce trips. Ordinary timetable information usually won’t help here.
- Expect changes. A vehicle swap, weather or technical reasons can shift everything at short notice. Check the state again the day before.
- Arrive early. At special trips, good spots fill up faster than in everyday operation.
How to systematically find dates like these is described in the guide to finding special trips and charter trains. Anyone interested in heritage railway operation as a whole will find a fitting overview in the article on heritage railways and their dates. And because voluntary structures almost always stand behind operational historic vehicles, it’s worth looking at the overview of railway societies in Austria and the DACH region.
Operational status is subject to change
Whether a historic vehicle is operational depends on deadlines, spare parts and voluntary work. Statements about availability and dates are always snapshots – check them with the operator before every trip out.
Why railbuses were built at all
To place a vehicle like the VT 10, it helps to look at the problem it was meant to solve. Branch lines faced the same dilemma for decades: too few passengers for a train with a locomotive, but too many to simply abandon the line.
A classic train ties up a lot of effort in this situation. The locomotive has to be run round at every end point, staff are correspondingly tied up, and a heavy train still uses energy even when only a handful of passengers are on board.
The railbus turned this equation around. It’s lightly built, carries its traction unit on board, needs no overhead line and gets by with minimal staffing. A driving cab at both ends further means no running round, no shunting, no extra track infrastructure at the terminus. This exact combination kept many branch lines alive for decades.
That modern diesel railcars carry the same basic ideas forward – a single vehicle or short unit, traction on board, a driving cab at both ends – shows how sound the concept was. The VT 10 therefore stands not just for a single vehicle, but for an operating idea that still shapes regional traffic today.
Photo tips for historic railcars
Think about the surroundings
A historic vehicle looks out of place against a modern backdrop. A plain background lets the shapes speak.
Document the markings
A close-up of the full number makes the sighting verifiable and is later worth more than another overview shot.
Use the dwell times
Special trips often have longer stops. Use them for calm shots rather than hectic pass-by pictures.
Stay on public ground
Platforms and public paths are enough. Tracks, operational railway land and stabling areas are off limits – even at special events.
Common mix-ups
It points to the VT 10 if …
- a small, lightweight railcar with no pantograph stands before you
- the marking shows Class 5010
- the keeper marking reads A-GKB
- the vehicle is out as part of a special trip
Look more closely if …
- you see a historic vehicle with no legible marking
- several museum vehicles are stabled together
- the vehicle is running coupled with other historic carriages
It's not the VT 10 if …
- a pantograph sits on the roof
- the entrance is low-floor and step-free
- the class marking begins with 5022 or 5047
The most obvious mix-up candidates among diesel railcars are Class 5047 and Class 5022 (Desiro Classic) – both more modern, larger and running in regular service. Anyone interested in the GKB’s historic vehicle world as a whole will find the steam-powered counterpart in the same fleet with the GKB Class 29.
Conclusion
The VT 10 is two things at once: an endearing piece of branch-line history and a perfect textbook example for the European vehicle number. Anyone who has once read 9581 5010 002-1 A-GKB block by block will afterwards be able to decode any Austrian marking – from a railbus to a modern multiple-unit set.
In short
A small diesel railcar with no pantograph, Class 5010, keeper GKB: that's the VT 10. It doesn't run in the regular timetable – anyone wanting to see it plans around special-trip dates, not around a location.
Record special trips and rarities
Date, occasion, number and location in one place – for historic vehicles that's exactly the information that matters.
Summary
- The VT 10 belongs to the vehicle world of the Graz-Köflacher Bahn and represents the railbus generation on Austrian branch lines.
- Its twelve-digit number is a textbook example of how much information sits in a single vehicle marking.
- As a historic vehicle it's not a candidate for spontaneous sightings but for trips planned around a date.
- Anyone who documents an encounter is recording an event that can't simply be repeated at will.
Frequently asked questions
What is the GKB VT 10?
A historic diesel railcar of railbus design belonging to the Graz-Köflacher Bahn, carried under Class 5010. Light railcars like this were developed for lines with low traffic volumes, where a full train with a locomotive would simply have been uneconomical. Today the vehicle is seen mainly at special trips.
What does the number 9581 5010 002-1 A-GKB mean?
It's the full European vehicle number. 95 is the type code, 81 the country code for Austria, 5010 the class, 002 the running number and the 1 at the end the check digit. A-GKB names the keeper's country and the keeper itself, here the Graz-Köflacher Bahn.
What does the 5 in Class 5010 tell you?
It encodes the vehicle type. In the Austrian scheme, traction vehicles are designated with "Reihe" (class) plus a four-digit number: 1 for electric locomotives, 2 for diesel locomotives, 4 for electric railcars, 5 for diesel railcars. The system also applies to private-railway vehicles, which are fitted into this numbering scheme.
What exactly is a railbus?
A light railcar that borrows construction principles from road-vehicle building to reduce weight and operating costs. Railbuses were developed for branch lines with low passenger numbers. Characteristic features are the lightweight car body, the built-in combustion engine and the complete absence of overhead-line equipment.
Where can I see the VT 10?
At special and heritage trips. Historic vehicles don't appear in the regular timetable but are deployed on announced dates. Anyone planning an encounter should therefore go by event calendars and the operator's announcements, not by ordinary timetable information.
How do I tell it apart from a modern diesel railcar?
By the styling and the marking. Current ÖBB diesel railcars have low-floor entrances, large bonded windows and modern front ends. A railbus looks smaller, more angular and noticeably older. The keeper marking A-GKB instead of an ÖBB marking is another unambiguous signal.
Does the GKB belong to the ÖBB?
No. The Graz-Köflacher Bahn is an independent railway company with its own fleet. Its vehicles carry the keeper marking GKB in their markings. They're nonetheless carried under the same European numbering scheme, because that scheme applies to every vehicle on the network.
Why is it worth documenting historic vehicles?
Because sightings like this can't be repeated. You'll see a vehicle in regular service again tomorrow; a special train runs on one particular day and then not again for a long time. Date, occasion, location and vehicle number turn a photo into a solid record.
Log your sighting of the GKB VT 10 / 5010
Date, location and vehicle number logged in seconds – and visible to the community.
Related classes
GKB Class 29
The GKB Class 29 belongs to the historic steam fleet of the Graz-Köflacher Bahn. Here's how to read its vehicle number and plan a sighting.
DMUÖBB Class 5047
The Class 5047 is the ÖBB's single-section diesel railcar for branch lines. Here's how to recognise it and tell it apart from the two-part Class 5022.
DMUÖBB Class 5022 (Desiro Classic)
The Class 5022 is the ÖBB's two-part diesel railcar for non-electrified lines. Here's how to recognise it and tell it apart from the Class 5047.
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