Alteinsee

Alteinsee is a high-alpine lake above Arosa in the Swiss canton of Graubünden, sitting at roughly 2,251 m. It occupies the Altein Tiefenberg plateau in the Strela range, south of the Aroser Stausee reservoir. Walkers who reach its shore get wide views over the surrounding peaks, and the lake is the reward of one of the valley's best-known day hikes.

Where is Alteinsee?

The lake lies high above the village, at about 46.75 N, 9.70 E. There is no road and no cable car to the water, so the last stretch is on foot along marked trails. Nearby highlights include the Altein waterfalls and the smaller Grüenseeli.

How do you hike to Alteinsee?

The classic route begins at Untersee in Arosa. It heads toward the hamlet of Isel, where you meet the Stausee reservoir, continues to Grüenseeli and then climbs to the plateau with Alteinsee. The way back passes the Altein waterfalls.

This "four-lake" loop is about 15.5 km, close to six hours on foot, with around 950 m of climbing. Regional guides grade it anywhere from "a little challenging" to "difficult", so plan a full mountain day. A shorter option of roughly 12 km and five hours links the lake and waterfalls with a circuit around the Aroser Schiesshorn. Longer variants exist for fit, surefooted hikers.

What will you see?

• A calm lake above 2,200 m, ringed by alpine pasture.
• Mountain views across the Strela range and the hills around Arosa.
• The Alteiner Wasserfälle, thundering on the ascent or descent.
• Three more waters along the way: Untersee, the Stausee and Grüenseeli, so one outing covers several lakes.

If you still have energy on the Schiesshorn circuit, an optional side climb leads to the 2,431 m summit.

When should you go?

The trails are walkable in summer and early autumn, once the snow has melted. At this altitude weather turns quickly, so check the forecast in the morning and pack a warm layer, a rain jacket and proper hiking boots. In winter the area is a different proposition: it generally calls for gear and mountain experience, and many paths are not maintained for walkers.

Frequently asked questions

How high is Alteinsee?

About 2,251 m above sea level.

Can you drive to the lake?

No. Only hiking trails lead there; the easiest starting point is Untersee in Arosa.

How long does the hike from Arosa take?

The four-lake loop takes about six hours (around 15.5 km). The Schiesshorn variant is roughly five hours and 12 km.

Is the route easy?

No. With about 950 m of ascent and a medium to hard rating in trail guides, good fitness is needed.

What else is on the way?

The Altein waterfalls, Grüenseeli, the Stausee and Untersee, plus peak views around Arosa in clear weather.