Overview
The S25 is a short, steep-minded climb dressed up as an ordinary commuter line — it starts at the water's edge in Rorschach Hafen and finishes high above the lake in Heiden, and in between it does all the work a mountain railway usually charges a premium for.
There's no pretence of grandeur here, no observation-car theatrics. It's a working link between the Bodensee shoreline and a hilltop town in the Ostwind region, and that honesty is exactly the appeal: you get the view without the fuss.
Treat it as a journey rather than a transfer. Whichever direction you ride it, the change in altitude and outlook happens quickly enough that it's worth putting the phone away for the length of the trip.
Key facts
| From | Rorschach Hafen |
|---|---|
| To | Heiden |
| Operator | AB-rhb |
The route: from harbourside to hilltop
Rorschach Hafen sits directly on the Bodensee shoreline, so the S25 begins about as low and as flat as the region gets. From there the line climbs steadily towards Heiden, a town set well above the lake in the Ostwind region, and the character of the landscape changes with it — water and harbour give way to rising ground, open slopes and the kind of wide-angle outlook that only comes from gaining height.
It's not a long journey in distance, but it's a journey of contrast rather than monotony. You leave at lake level, surrounded by the ordinary business of a harbour town, and arrive somewhere that feels distinctly elevated, both literally and in mood — quieter, airier, and with the lake now something you look down on rather than stand beside.
Timetable & how to book
Services on the S25 vary through the year, with the operator, AB-rhb, adjusting frequency according to season and demand. Because of that, it's not a line where you can assume a fixed pattern of departures — always check current times directly with AB-rhb before you travel.
Booking works the same way: rather than relying on guesswork or older timetables you might find elsewhere, go straight to the operator for up-to-date departure times and any advance-purchase options. This is particularly worth doing if you're planning a specific connection at either end, in Rorschach Hafen or in Heiden.
Fares & classes: what actually differs
As with the timetable, exact fares aren't something to guess at — check these with AB-rhb directly, since they'll have the current structure for the S25 and any regional passes that might apply.
What's worth knowing in general terms is how classes typically differ on a line like this: a higher class usually means a more comfortable seat, a bit more space to stretch out, and often a layout designed to make the most of the windows. A standard class ticket will get you the same journey and largely the same view, just with a simpler seat and less elbow room. Neither class changes the scenery outside — the climb from Rorschach Hafen to Heiden is the real product here, and it's on offer whichever ticket you buy.
Which side to sit for the best views
Because the S25 spends its journey gaining height away from the lake, the side that faces the Bodensee is generally the one to choose if views are your priority — that's where you'll get the sense of the water dropping away as the train climbs towards Heiden.
If you're travelling the other direction, from Heiden down to Rorschach Hafen, the same logic applies in reverse: keep an eye on which side the lake appears on as you begin the descent, and sit there. On a short journey like this, it's worth deciding before you board rather than trying to switch seats mid-route.
Onboard experience
Expect the practical comforts of a well-run regional line rather than a themed experience: clear windows designed to let the changing landscape do the talking, and a general sense that the train exists to move you between lake and hilltop as pleasantly as possible.
Given the modest length of the journey, don't expect an elaborate onboard catering operation — this is the kind of line where the scenery is the main event, and any refreshments are best sorted before boarding in Rorschach Hafen or after arrival in Heiden. Check with AB-rhb if onboard catering is something you're relying on for a particular service.
Best season to ride
The Ostwind region changes considerably across the year, and a lake-to-hilltop line like the S25 will feel different depending on when you ride it. Warmer months tend to bring clearer, longer views back over the Bodensee and a livelier atmosphere at both ends of the line, while cooler seasons can bring a starker, quieter landscape and crisper visibility on the right day.
There's no single 'correct' season — it depends on whether you want a lively summer outing with the lake glittering below, or a quieter off-season ride with fewer people and a more contemplative feel. Either way, dress for a noticeable difference in temperature and wind between lakeside Rorschach Hafen and elevated Heiden.
Alternatives & onward connections from Heiden
Heiden functions as a natural endpoint for onward exploration of the Ostwind region once you've made the climb from the lake. From there, travellers typically look to local connections to continue further into the region or to loop back down towards the Bodensee shoreline by a different route.
If you'd rather not retrace your steps on the S25, it's worth asking AB-rhb about alternative routings or connecting services from Heiden — regional operators in areas like this often have more than one way of linking hilltop towns back to the lake, even if the S25 itself is the most direct.
A little history and context
Lines like the S25, linking a lakeside harbour to a hilltop settlement, tend to have their roots in an era when getting goods and people up from the water to elevated towns was a genuine engineering challenge rather than a scenic bonus. What began as practical infrastructure has, over successive eras, become as much a way of experiencing the landscape as a way of commuting through it.
AB-rhb's continued operation of the route keeps that dual identity alive: still a working regional service for people in Rorschach Hafen and Heiden, but increasingly appreciated by visitors for exactly the qualities — the climb, the shifting views, the contrast between lake and hilltop — that made it worth building in the first place.
Common questions
- Do I need to book the S25 in advance?
- It depends on the season and demand, so check directly with AB-rhb. Services vary through the year, and they'll have the current position on whether advance booking is advisable or necessary.
- Which side of the train gives the best views of the lake?
- Sit on the side facing the Bodensee. Travelling from Rorschach Hafen to Heiden, that means keeping the lake in view as the train climbs; heading the other way, look for it on the descent.
- Is there a difference between classes on the S25?
- Generally yes — a higher class typically offers a more comfortable seat and more space, while standard class is simpler. The view and the route are the same either way. For exact fares and class options, check with AB-rhb.
- What's the best time of year to ride the line?
- It depends what you want. Warmer months tend to give clearer, longer views over the lake and a busier feel; cooler months bring a quieter, starker landscape. Both have their appeal in the Ostwind region.
- Can I connect onward from Heiden without doubling back?
- Ask AB-rhb about alternative regional connections from Heiden. Many hilltop towns in the region have more than one link back down to the lake, even if the S25 is the most direct route.
On the map
Sources & method
- OpenStreetMap route=train (ODbL) — route
See our methodology for how Head Your Way sources and reviews travel data.