Key takeaways
- The 23.10 is a DR new-build locomotive: 113 machines, built 1956 to 1959 by LKM Babelsberg for medium-weight passenger service.
- Fastest way to identify it: one leading axle at the front, three coupled axles, one trailing axle at the rear – plus a tender.
- 23.10 and 35.10 are the same locomotive: the Deutsche Reichsbahn renumbered the class in 1970 as part of its computerised numbering switch.
- No regular service any more: whatever runs today runs as a museum, special or heritage locomotive.
- The main risk of confusion is with the West German Class 23, which follows the same basic idea but is a separate design.
Contents
Fact file
| Vehicle type | Tender passenger locomotive, new-build locomotive of the Deutsche Reichsbahn |
|---|---|
| Wheel arrangement | 1'C1' h2 – one leading axle at the front, three coupled driving axles, one trailing axle at the rear |
| Manufacturer | LKM Babelsberg |
| Years built | 1956 to 1959 |
| Quantity | 113 locomotives, running numbers 23 1001 to 23 1113 |
| Maximum speed | 110 km/h forward, 50 km/h in reverse |
| Power output | around 1,250 kW |
| Renumbering | from 1970 as Class 35.10, numbers 35 1001 to 35 1113 |
| Current status | no regular service, individual locomotives preserved in museums |
Identifying features
Is this really the class in front of you?
- Three coupled driving axles, with one single leading/trailing axle each before and behind – wheel arrangement 1'C1'
- A tender behind the locomotive, so no side water tanks along the boiler as on a tank locomotive
- Welded construction with smooth plates instead of the rivet rows of older regional-railway locomotives
- Small Witte-type smoke deflectors instead of the large plates of older designs
- Running number begins with 23 1 or – after the 1970 renumbering – with 35 1
- Always in front of light passenger trains on museum or special services, never in front of heavy freight trains
Updated: August 2026 – A steam locomotive with a tender, three coupled driving axles and one leading and one trailing axle each: that’s the basic pattern of the Class 23.10, the Deutsche Reichsbahn’s last new-build passenger locomotive. From 1970 the same machine ran as Class 35.10. This page shows you how to identify it, what’s behind the double designation, and how you can still get it in front of your lens today.
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What is the Class 23.10?
The Class 23.10 is a Deutsche Reichsbahn tender passenger locomotive with the wheel arrangement 1’C1’. Between 1956 and 1959, 113 machines with running numbers 23 1001 to 23 1113 were built by LKM Babelsberg. They were cleared for 110 km/h, produced around 1,250 kW, and were meant to replace the ageing regional-railway designs in medium-weight passenger service.
Historically, the class is a late arrival: it reached the rails at a time when diesel and electric locomotives were already displacing steam traction. Its career was correspondingly short. Today only individual machines survive as museum and heritage vehicles – there are no more scheduled workings in regular service.
How to read the class number of a German steam locomotive
The Deutsche Reichsbahn-Gesellschaft’s 1925 numbering scheme looks arbitrary at first glance, but follows a clear logic: the number range reveals the purpose and the design.
Read the first digit group
01 to 19 are express locomotives with a tender, 20 to 39 passenger locomotives, 40 to 59 freight locomotives. From 60 upward come the tank locomotives without a separate tender.
Note the number after the point
The sub-class narrows down designs within a class. The ".10" in the 23.10 marks the Reichsbahn's new-build locomotive as against the Bundesbahn's Class 23.
Add in the wheel arrangement
Numbers stand for leading and trailing axles, letters for coupled driving axles. 1'C1', then, means: one leading axle, three coupled axles, one trailing axle.
Once you’ve internalised this pattern, you can roughly place any German steam locomotive class without knowing it. The general system behind classes and vehicle numbers is explained step by step in the guide to identifying classes.
Rule of thumb for the first glance
Count the axles first and check whether a tender is coupled on. You can spot both even in poor light and from a great distance – boiler fittings and number plates you can check afterwards at your leisure.
The 1970 renumbering: why 23.10 became 35.10
In 1970 the Deutsche Reichsbahn switched its fleet to a computer-suitable numbering scheme. In the process, the Class 23.10 moved as a whole into the 35.10 range: 23 1001 became 35 1001, 23 1113 became 35 1113. Nothing changed technically.
In practice that means: older photos and literature list the machines as 23.10, later sources and most of today’s museum vehicles as 35.10. Anyone documenting a sighting should note the number that actually appears on the vehicle – not the one printed in a book.
| Feature | Class 23.10 (until 1970) | Class 35.10 (from 1970) |
|---|---|---|
| Running numbers | 23 1001 to 23 1113 | 35 1001 to 35 1113 |
| Railway administration | Deutsche Reichsbahn | Deutsche Reichsbahn |
| Technology | unchanged | unchanged |
| Typical use then | passenger and light express trains | passenger and passenger-train service until withdrawal |
| Current status | historical designation | designation of the surviving museum locomotives |
Document historical vehicles properly
Number, date, occasion and location – for museum locomotives, that's exactly where a sighting's value lies.
Where you’ll realistically find a 23.10 today
There’s no timetable listing this class. Anyone wanting to see it has to go the other way round: first find out where a surviving machine is based, then check whether and when it runs – boiler deadlines and workshop dates, for instance at the Dampflokwerk Meiningen, decide that.
These research routes work reliably:
- Event calendars of heritage railways and railway museums. Operable large steam locomotives are announced there, often months in advance.
- Society and operator pages. Whoever maintains a locomotive usually writes themselves about deadlines, workshop stays, or when it’s back under steam.
- Special-train lists and railway forums. The guide to special trains and special workings shows which sources are worthwhile and how quickly dates can change.
- Community sightings. What was reported yesterday is the best clue to what’s operable right now. How to contribute such reports yourself is in the guide to reporting sightings.
- Heritage-railway sections of large railway forums. The overview of heritage-railway research sums up where dates appear first.
House rules apply on museum sites and at special trains
Tracks, operational installations, turntables and sheds are not public areas. Barriers, staff instructions and designated photo spots are binding – even when the perfect shot would be a few metres further on. Photograph from publicly accessible areas; which rules apply at the track is summed up in the piece on safe distance at the track.
Photo tips for a steam locomotive with the 1’C1’ wheel arrangement
A steam locomotive is photographed differently from an electric one: the steam is part of the subject, the light determines the effect, and the train passes exactly once.
Choose a three-quarter view
An angle of around 30 to 45 degrees shows the front and the motion work at once. That very motion work with its three coupled axles is the identifying feature of this class.
Mind the background
Steam and smoke need a calm, ideally dark surface to stay visible. Against a bright sky, the plume disappears.
Use cold air
In low temperatures, the steam condenses more strongly and the locomotive looks more impressive. In midsummer, often only a thin haze remains.
Plan for a second chance
Special trains often run there and back. Use the first pass as a test run and the return trip for the actual shot.
The full technique – shutter speed, choosing a spot, dealing with backlight – is covered in the guide how to photograph steam trains. Anyone wanting to archive their photos properly afterwards will find a workable structure in the piece on the photo archive for spotters.
Common mix-ups
It points to the 23.10 / 35.10, when …
- you count three coupled driving axles with one leading/trailing axle each before and behind
- a tender runs behind the locomotive
- the construction looks smooth and welded, with no visible rivet rows
- the number begins with 23 1 or 35 1
Look more closely, when …
- the locomotive is standing in backlight or from behind and you can't reliably count the axles
- you see a new-build locomotive but don't know whether it's from eastern or western production
- the number plates are missing or painted over
It's not a 23.10, when …
- you count four or five coupled axles – then you're looking at freight classes
- water tanks sit alongside the boiler and there's no tender – then it's a tank locomotive
- the number begins with 38 – that's the Prussian P 8
The most common mix-up happens with the West German Class 23, which follows the same basic idea but is an independent design. If you only look at the wheel arrangement, you won’t get anywhere here – the number decides. It’s similarly ambiguous against the older Prussian P 8, which as a 2’C machine has a two-axle bogie at the front instead of a single leading axle. With freight classes such as the Reko Class 50.35, by contrast, five coupled axles stand out immediately.
Conclusion
The Class 23.10 is a vehicle you can be sure of from three features: wheel arrangement 1’C1’, tender, number 23 1 or 35 1. The double designation isn’t a technical difference, just the result of the 1970 renumbering. Today you’ll only encounter it in museums – and that’s exactly what makes every sighting worth documenting.
Bottom line
One leading axle, three coupled axles, one trailing axle, tender: that's the 23.10, or 35.10. It doesn't run to a timetable but to an event calendar – anyone wanting to see it researches through heritage railways and heritage societies.
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Summary
- The Class 23.10 was the Deutsche Reichsbahn's last attempt to modernise passenger service with a newly designed steam locomotive.
- For identification in the field, wheel arrangement, tender and running number are enough – boiler details you only need afterwards.
- The 1970 renumbering from 23.10 to 35.10 still causes confusion today: both numbers refer to the same 113 machines.
- Anyone wanting to see the class plans through heritage railways, heritage societies and special trains – not through the timetable.
Frequently asked questions
How do I identify the Class 23.10 with confidence?
By the wheel arrangement 1'C1': a single leading axle at the front, three coupled driving axles in the middle, a single trailing axle at the rear. Add to that the tender and the welded, smooth construction without the rivet rows of older regional-railway locomotives. The running number begins with 23 1 or 35 1.
Why is the locomotive sometimes called 23.10 and sometimes 35.10?
Because the Deutsche Reichsbahn switched its vehicles to a computer-suitable numbering scheme in 1970. In the process, the Class 23.10 moved into the number range 35.10. It's the same 113 locomotives – the designation just depends on which period someone means.
How many Class 23.10 locomotives were built?
113 locomotives were built, with running numbers 23 1001 to 23 1113, produced between 1956 and 1959 by LKM Babelsberg. How many of them still exist today, and in what condition, changes with overhauls, deadlines and society projects.
Does the Class 23.10 still run today?
Not in regular service. Individual locomotives are preserved in museums, some operable, some as static exhibits. There are no scheduled workings – runs take place as special trains, heritage-railway operation or at events.
What's the difference between Class 23 and Class 23.10?
The Class 23 was the Deutsche Bundesbahn's new-build locomotive in the west, the 23.10 the Deutsche Reichsbahn's in the east. Both pursued the same goal – a modern replacement for the old passenger locomotives – but are independent designs with different details.
How fast did the Class 23.10 run?
Its maximum speed was 110 km/h forward and 50 km/h in reverse. These figures apply to its former regular service. In today's museum operation, the actual speed is set by the current registration and the route, not by the datasheet value.
What was the Class 23.10 built for?
For medium-weight passenger service: passenger trains and light express trains on main and stronger branch lines. It was meant to replace older regional-railway designs like the Prussian P 8, but arrived in a period when diesel and electric locomotives were already displacing steam traction.
Where do I find dates when a 23.10 or 35.10 is running?
Through the event calendars of heritage railways and heritage societies, through special-train lists on railway forums, and through community sightings. There are no fixed dates – always check the current picture directly with the operator, because deadlines and workshop visits can change everything at short notice.
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Related classes
Class 23
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