Hike to Lai Blau at the Lukmanier Pass and Val Medel

Friday August 15, 2025 -- Today we did another successful trip into higher elevations to get away from the heat....

We have often been to the Lukamanier Pass between Cantons Ticino and Graubünden, and had seen on our maps that there was an alpine lake called Lai Blau (Blue Lake) at some 500 meters higher than the large reservoir lake at pass level (Santa Maria Lake). Urs has long talked about a hike up to that lake, so that is what we did this day. It takes over two hours to hike from the pass to the little alpine lake.

There has been construction work going on for a very long time on the pass road on the east side of Santa Maria Lake (they are building a gallery to try to keep this pass open to traffic for as long as possible in winter), and whereas there used to be a bus stop at the level of the dam on the north end of the lake, this bus stop is no longer serviced, and therefore we had to walk an hour longer to get to the next bus stop, either back to the pass or down the Medel Valley to the next possible bus stop. (We chose the latter, as we don't generally like to walk back the same way we came). This turned out to be a five-hour hike, but at least we were lucky once again with lots of cool breeze the whole day.

What we hadn't anticipated was the large number of people who did the same hike to the lake... we had really thought this was an out-of-the-way location, but because it was a holiday, and because people traveling by car over the pass can park and do the round-trip hike (although a long one), we just had the bad luck that everyone decided to descend from the lake at the same time!

It only takes just over three hours to get to the Lukmanier Pass from home, but although the train to Bellinzona is quick, it's the very long bus ride up the Blenio and Santa Maria Valleys which seems to take forever! Here is where the bus heads up the Santa Maria Valley from Olivone, which is still in shadow of the mountains at 9 a.m. 

About two-thirds up the valley near Acqua-Calda, we pass this large upper plain called Pian Segno. This is interesting for us because we passed through here when we descended that hillside from upper left back in July of 2023 (those photos are HERE).

As the bus now approaches the Lukmanier Pass (also known as the Passo di Lucomagno, because this is right at the border between Cantons Ticino and Graubünden), we can see where we are going to hike up to. (Where the arrow is).

Starting at the Lukmanier Pass (after a bus ride of over an hour from Biasca), we see that it is a 2¼-hour hike to reach the little alpine lake called Lai Blau (Blue Lake).  We started here at 9:30 (having left home at about 6 a.m.!)

This large reservoir lake at the Lukmanier Pass is called "Lai da Sontga Maria", or Santa Maria Lake. We are hiking clockwise around this lake, detouring to Lai Blau at the arrow, descending back to Santa Maria Lake, and continuing to the dam on the north end of the lake. 

Starting at about 9:30 at the Lukmanier Pass, we got to Lai Blau at just after noon (so just over 2½ hours). We spent almost an hour up there, then descended the same way to Santa Maria Lake, walking via the dam to the next available bus stop in the Medel Valley (the one at the dam is unfortunately no longer serviced). We caught the 16:24 bus back to the pass for the 3¼-hour trip back home.  In all, this was a five-hour hike!

A wide road leads around the south side of Santa Maria Lake, crossing the Canton Borders a couple of times! (A bit in Ticino, then in Graubünden...)

Looking northwards across the lake, we see the mountains of the Surselva Valley past the dam. (The water which leaves the dam is called the Medel Rhine River, flows northwards along the Medel Valley to join the Vorderrhein River at Disentis). 

At the southwest end of the lake, we join the mountain trail. 

This cute little suspension bridge crosses the Medel Rhine River where it enters Lake Santa Maria at its south end, coming down from the Cadlimo Valley. At this point we are back in Canton Ticino!

Looking down from the little suspension bridge over the Medel Rhine River. (Rein da Medel in the local language).

Making our way along the west side of Lake Santa Maria, toward the side valley where we start the ascent to Lai Blau. Across the lake is the pass road, where construction to build protective galleries has been going on for quite a long time. Behind me is the wider road which we will follow when we come back down from the lake. 

After a little over an hour walking along the lakeshore, we now head into the side valley (Val Rondadura) and start our ascent to Lai Blau. 

On very hot days I take along a face-cloth which I soak in the very cold waters of the mountain rivers, and use it to cool off my head!

A look behind us to the Lukmanier Pass as we start on the long ascent to Lai Blau (about 1½ hours) 

A look to the back of Val Rondadura. The mountains are magnificent. Unfortunately we were not alone in climbing up this trail. A few people passed us on the way up. 

The cows are grazing here at the higher alpine pastures (Alp Rondadura). 

The cows have the best views in the summer!

These waterfalls are from the river that leaves Lai Blau

Another look back to Lake Santa Maria from Alp Rondadura. 

Sometimes a frog will hop over the trail. This one was huge, compared to the little forest frogs which we saw on our most recent hike on Mt. Bürgenstock. 

And now we have reached Lai Blau (Blue Lake) at just after noon time! (It took us just over 2½ hours after starting at the pass, for an ascent of about 500 meters from where we started in the side valley.)

First thing we have to do is find a really nice spot to eat our picnic lunch (and for me, I had to have a nap!). Up ahead on the green hilltop is where we spent about an hour. 

Panorama photo of the lake, Lai Blau

VIDEO:

360-degree panorama view

Urs found a different spot so I could have a nap... There were about a dozen people up here but they were pretty spread out around the lake so we didn't notice them at this point. 

Wandering around a bit before heading back down the mountain. 

A great viewpoint for a look down to the pass road, and the Santa Maria Valley in Canton Ticino. 

A bit of colour up here in the otherwise barren landscape!

At 1:20 p.m. we decided to head back down (We wanted to catch the 16:24 bus and still had about 2½ hours to walk, so not a lot of extra time).  Right then all the other groups started their descent as well. We would have been smarter to wait up here for another 15 minutes, and let the others get ahead. 

All the other people who had hiked up to the lake ended up walking down at the same time we did! We regretted not spending an additional 15 minutes up at the lake to give the other hikers time to descend before we started!

Hurrying down the mountain as we tried to stay ahead of the other hikers! Here we are back at the Alp Rondadura where the cows were grazing. 

VIDEO:

It's always nice to hike with the sound of cowbells around us!

Hurrying down the mountain as we tried to stay ahead of the other hikers!

Another look up the side valley as approach lake level. 

Here all the other hikers headed back to the parking lot at the pass, whereas we were the only ones heading north toward the dam. 

A wider dirt road leads to the dam.

It took about 20 minutes along this road to get to the dam. Such a shame that the bus stop on the far side of the dam is no longer serviced! 

We would have had the option to cross the dam and walk back to the pass on the other side of the lake next to (on top of?) the motor vehicle gallery, but we didn't think that would be very pleasant. 

We arrived at the dam at 14:35. Those clouds look cool! We didn't go across the dam, but continued right away on the path on the west side of the dam. 

The view down the Medel Valley from the edge of the dam. Our trail follows the left hillside down to the cable-car station in the center of the photo. (And then further on down the valley). 

Winding down the trail at the north side of the dam. The dam was built between 1964 and 1968.

This is the military base station of a large cable-car way up to the summit of the mountain on the east side of the large lake. 

A break at the old Roman Bridge which crosses the Medel Rhine River at the military cable-car station.

And off we go on the final stretch of our walk to the next bus stop down the Medel Valley. About 40 minutes along this road, and I quite enjoyed this walk. It was easy after our long ascent to the lake, and there was plenty of wind!

Up ahead we can see the path that leads up to the bus stop on the vehicle road. But on the left at the valley bottom is a small farm and a chapel we are hoping to view. This is called Caplutta Sogn Gagl, which is the Romantsch name for St.Gallen Chapel. 

We have to cross the Medel Rhine River to get to the Sogn Gagl Chapel, which unfortunately turned out to be locked. (So we filled up our bottles at that water fountain, and headed to the bus stop). 

The information on this panel states that the Alp (farm) and chapel belong to the Monastery in Diesentis. The chapel was built in the 11th or 12th Century. There are apparently valuable frescoes from 1350 depicting The Last Supper inside. It was disappointing that we didn't get to see them. Apparently there used to be a church bell, but it was stolen in 2010. 

A look up the valley toward the Santa Maria Dam

The "Rein da Medel" river makes its way down the valley to join the Vorderrhein River (Rein Anteriur) at Disentis. (This is one of many of the tributaries of the major Rhine River). 

Our bus arrives at 16:24 for the trip back over the Lukmanier Pass, down the Santa Maria Valley to Olivone, and then down the Blenio Valley to Biasca. 

What our hike looks like on Google Satellite Maps. 

From the bus, a look down the Medel Valley toward Sogn Gagl. 

Passing Santa Maria Lake again at the Lukmanier Pass. 

Heading back down the Santa Maria Valley. 

Down the Santa Maria Valley, the further line of mountains are the Adula Alps, where the other major Rhine River (Hinterrhein) has its source on the other side (where we had spent two days earlier this week). 

The bus winds its way down into the town of Olivone, which is at the junction of the Blenio and Santa Maria Valleys. That pyramid-shaped mountain that looms at the junction of three valleys is called Mt. Sosto. 

Those peaks are further down the Blenio Valley. 

Along the way, the bus passes by the former Cima Norma Chocolate Factory in Dangio. 

A look at the village of Dangio and up the Blenio Valley.

Approaching Biasca at the junction of the Blenio and Leventina Valleys. (From Biasca, a train southwards to Bellinzona, then the fast train northwards through the Gotthard Base Tunnel). 

All the hikes we have done in the region of the Blenio and Santa Maria Valleys, near the Lukmanier Pass. 

Location of the Lukmanier Pass within Switzerland.