A vanishing green lake.

Grüner See or Green lake is a beautiful lake, hidden amongst the Hochschwab mountains and named for its clear, emerald-green water. It is located in southeastern Austria, but as an intermittent lake it is not always there.

During the winter Grüner See almost completely disappears, leaving behind a puddle of about 1 – 2 m in depth and a park with hiking trails. It returns again in the early spring, when the snow from the surrounding mountains melts and flows into the lake valley. The pure, cold snow melt makes for some of the clearest water I’ve ever seen and gives the lake its signature colour. It really is as green as the name suggests, with varying shades of green, depending on the depth of the water. In some shallow parts it is almost neon green and all the green shades very surprisingly intense, like a saturated photograph. While I’m at it, there’s also a similar Red lake in Romania, which is not an intermittent one, but reflects red because of the red limestone on the bottom and comes with an interesting legend.

Anyhow, back to Grüner See: you can walk the whole way around the lake and, because its depth varies over the year, there are multiple trails at different heights. Since the water is so clear, you can actually see the submerged hiking trails crossing the lake bed and every single blade of grass under the water. It looks like you could step right through the looking glass into another world and walk on the meadow under the water, which is what Grüner See is famous for.

Before 2016 it was possible to scuba dive in the water and swim amongst the submerged trails, benches and even an occasional tree, which was a magical experience (you can see a video here). That is how the lake became an Internet sensation and the influx of tourists significantly damaged the ecosystem, so any kind of water sports activity is now strictly forbidden to protect the environment. Nonetheless, it is still an awesome place to visit and the perfect spot for a picnic.

Grüner See is also home to a large variety of animals, particularly birds. You can see different species depending on the season, but I am not much for bird watching myself, so I cannot tell you which ones. We did see a duck though, as any visit to a lake is not complete without seeing at least one duck.

Impressions of Grüner See

Me and my boyfriend visited Grüner See during our 1st of May trip in 2019 and walked the whole way around it. Since we were there in early May, the water was not quite so deep yet, but there was more than enough of it to constitute a real and very picturesque lake, particularly against the backdrop of the mountains. It was a bit cold and it started raining towards the end, but we are definitely coming back with friends for a picnic during the summer months.

Getting there: Grüner See is located above Graz and the nearest town to it is called Tragöß. It is quite easy to find: the signs for it appear around Kapfenberg and you can follow them the rest of the way. It is also on Google maps, here. You’ll find a huge parking lot with toilets upon arrival and parking there for the whole day will cost you exactly 4 €, which also serves as an entrance fee (as of May 2019). From there you need to walk to the lake itself, which is an easy hike and takes less than 20 minutes. The best season to visit is from April to August, because the water begins to recede in July. Grüner See is said to be the most beautiful in May to mid-June, when the water reaches its peak depth.