Hiking trail

To the Rhine source: Oberalp Pass – Lake Toma

· 8 reviews · Hiking trail · Switzerland
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  • Tomasee, Lai da Tuma, Rheinquelle, Tgina dil Rein
    / Tomasee, Lai da Tuma, Rheinquelle, Tgina dil Rein
    Photo: Heidi Meier, Sedrun Disentis Tourismus
  • / Die schönsten Wanderungen in Graubünden: Rheinquelle (Disentis Sedrun)
    Video: Graubünden
  • / Die Wanderung zum Tomasee beginnt
    Photo: Heidi Meier, Sedrun Disentis Tourismus
  • / auch Ziegen sind unterwegs
    Photo: Heidi Meier, Sedrun Disentis Tourismus
  • / der süss duftende Türkenbund am Wegesrand
    Photo: Heidi Meier, Sedrun Disentis Tourismus
  • / Alpenrosen schmücken die Hänge
    Photo: Heidi Meier, Sedrun Disentis Tourismus
  • / Kühles Nass nach der Anstrengung
    Photo: Heidi Meier, Sedrun Disentis Tourismus
  • / Glück hat, wer hier nicht auf weitere Wanderer trifft
    Photo: Heidi Meier, Sedrun Disentis Tourismus
  • / Aus Zwei wird Vier
    Photo: Heidi Meier, Sedrun Disentis Tourismus
  • / Viel Platz zum Picknicken
    Photo: Heidi Meier, Sedrun Disentis Tourismus
  • / Tomasee
    Photo: Heidi Meier, Sedrun Disentis Tourismus
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The shortest way to the Rhine source, to the beautiful Tomasee.
8 km
4:00 h
468 m
468 m

Lake Toma, the source of the river Rhine, is a special place. Even the travelling Benedictine monk of the Disentis Cloister, Father Placidus Spescha (1752-1833), already mentioned the Tomasee in his description of the Tujetsch valley as follows: "This 200-foot-wide and 400-foot-long lake is the basin from which the anterior Rhine originates. It is a beautiful area and therefore worthy of being the source of such a river."

The lighthouse: The former front light of Hoek van Holland, the 14-meter-high lighthouse that once stood at the Rhine estuary for seventy years, now stands as a harbinger of the Rhine source on the Oberalp Pass. The replica creates a first connection to Rotterdam at the other end of the Rhine. The lighthouse delights numerous mountain pass visitors and hikers in the summer as well as skiers in winter.

Lai da Tuma / Lake Toma: The 1230-kilometer journey of the Rhine begins here at the Rhine source. Much of what happens here has an influence on the river’s course. Therefore, the inhabitants of the municipality of Tujetsch - the land on which the Rhine source lies – take great care of their natural wonder. The mighty Rhine glacier once covered the entire Surselva region during the last ice age. The mountain landscape of the Oberalp Pass, formed by glaciers, is the source region of ​​the anterior Rhine (Vorderrhein). The stream of ice has long since melted away, leaving a basin in which Lake Toma is embedded into the valley of Six Madun at the foot of Piz Badus. At 2345m above sea level, the lake is a jewel among Swiss mountain lakes - unique in its beauty, magic and importance.

Oberalp Pass: The Oberalp Pass – called the "Alpsu" in Romanic - is the connection between Disentis in the canton of Graubünden and Andermatt in the canton of Uri. The highest point of the mountain pass is located at 2044m above sea level. From Disentis to Andermatt, the mountain pass is 32km long. In the Middle Ages the mountain pass allowed the Grisons access to pig and goat markets in the cantons of Uri and Ticino. Through the construction of today's road in the years 1862/63, the traffic over the Oberalp increased greatly. The romantic stagecoach age was born. The horse-drawn carriages only disappeared in 1925 when cars were introduced in Graubünden. The road is only accessible during the summer. In winter, travellers have to use the Matterhorn Gotthard Railway. The mountain pass is a popular starting point for skiers, ski tours and snowshoe hikers.

The railway line was put into service in 1926. During the first 16 years, before electric locomotives, steam trains ran only in the summer. The slowest express train in the world, the Glacier Express, also runs over the Oberalp Pass, connecting the Matterhorn village Zermatt with St. Moritz and Davos.

Author’s recommendation

In July, alpine roses and sweet-smelling martagon lilies bloom along the edge of the trail.

Overnight guests with a guest card can travel by train between Disentis and the Oberalp Pass free of charge. User
Heidi Meier
Updated: June 03, 2020

Highest point
Tomasee, 2368 m
Lowest point
Abzweigung Passtrasse, 1981 m
Best time of year

Rest Stop

Maighels hut

Safety information

The hike can only be done from approximately mid-June. However, until the end of June occasional fields of snow may still be found in the upper part of the trail. Inexperienced hikers should calculate an additional hour of hiking time.

The trek cannot be undertaken with a pram or by bike.

There is no place for meals or refreshments at the lake.

Tips, hints and links

Train timetable



Oberalppass (2040 m)
46.659914, 8.671059
46°39'35.7"N 8°40'15.8"E
32T 474833 5167425



Turn-by-turn directions

The hike begins at the lighthouse on the Oberalp Pass. At first we walk along the mountain pass road and then follow a trail to Val Maighels. At point 2056, we branch off to the right and ascend in a zig zag up the mountain. As soon as we have left the last rocky bends behind us, we reach the lake. The return route follows the same path.


all notes on protected areas

Public transport

Public transport friendly

By train from Andermatt or from Sedrun to the top of the Oberalp Pass.

Getting there

By car from Andermatt or from Sedrun to the top of the Oberalp Pass.


Parking spaces are available at the top of the mountain pass (free of charge).


46.659914, 8.671059
46°39'35.7"N 8°40'15.8"E
32T 474833 5167425
Arrival by train, car, foot or bike


Hiking equipment is recommended.

Questions & Answers

Question about Janine Fellmann · June 24, 2020 · Community
ist ein weg 4std?
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Answer by Manuela Kroll · June 25, 2020 · Community
Für den Weg in eine Richtung passt das
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Question about Ir Hu · June 17, 2020 · Community
Hallo Heidi Weisst du, wie die aktuelle Situation betreff Schneefelder aussieht? Wir planen diese Wochenende eine Wanderung zum Tomasee und auf die Maighelshütte. Es sind eben auch Kinder dabei. Danke für die Antwort.
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Answer by Heidi Meier · June 22, 2020 · Sedrun Disentis Tourismus
Bin zu spät mit der Antwort......der Weg ist nun gut begehbar. Hoffe dass die Wanderung gelungen ist Heidi
Question about Tamara Mojita · June 09, 2020 · Community
Ist der Weg zum Tomasee jetzt frei von Schnee und man kann dort hin wandern?
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Answer by Heidi Meier · June 10, 2020 · Sedrun Disentis Tourismus
Zur Zeit hat es noch Schneefelder auf dem Weg, die gefährlich werden können. Ausserdem hat es auf der Höhe des Sees in den letzten Tagen geschneit. Um den See so erleben zu können wie er auf den Prospekten abgebildet ist empfehle ich, bis Anfang Juli zu warten.
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Pascal Telle
October 27, 2019 · Community
Vorsicht! Der Start des weges ist sehr schlecht angeschrieben! Es geht zerst auf einem Wanderweg der Strasse entlang abwärts! Die Wanderung ist superschön!
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Done at October 26, 2019
Photo: Pascal Telle, Community
Peter Sailer
August 26, 2019 · Community
Tolle Tour bei genialem Wetter am Sonntag
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Done at August 25, 2019
Bastian Bodyl
October 02, 2018 · Community
Schöne Wanderung zur Rheinquelle. Auch mit wenig Ausdauer gut machbar, man sollte jedoch trittsicher sein. Es gibt einige Stellen, bei denen man aufpassen muss. Der See ist wunderschön gelegen und man kann dort auch fischen. Im Herbst ist die Wanderung sehr schön, wenn das Grass und die Heildelbeeren schon herbstlich verfärbt sind. Der See liegt auf über 2300müM, mann sollte also allfällige Schneefälle berücksichtigen.
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Done at September 30, 2018
Photo: Bastian Bodyl, Community
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Photos from others

+ 30

8 km
468 m
468 m
Public transport friendly Round trip Cultural/historical value Botanical highlights


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