The largely undeveloped shores and adjacent wetlands of Lake Altaussee provide habitats for numerous animal and plant species and have been under nature conservation since 1959.

The Austrian Federal Forests own Lake Altaussee, which is a popular excursion destination due to its beautiful location.

To the east, the Trisselwand (1754m sea level) features a rock face that rises approximately 600 meters high.

On the northeastern shore, the Seewiese marks the beginning of a trough valley that leads over the Hochklapfsattel to the plateau of the Totes Gebirge.

To the south, the Tressenstein (1201m above sea level) follows, while the village of Altaussee in the hilly area of the Aussee Basin is situated to the west.

The deepest point is a spring funnel near the north bank, which reaches a depth of 73m, while the water volume measures 72.7 million cubic meters.

It carves its path between the rock barrier of the Plattenkogel and the alluvial fan of the Augstbach, which acts as a natural dam for the lake.

The resulting overpressure causes a large jet of water to shoot out of the cave portal of the Liager hole in a high arc.

Scattered around the lake, one can observe remnants of terminal and lateral moraines, offering glimpses into the region's glacial history and the shaping of its surrounding landscape.

About 16,000 years ago, a powerful readvance of the glacier occurred and filled the basin once again, giving it its current form.

As the ice eventually disappeared entirely, the alluvial cone adjusted to accommodate the present lake level.

The Schönberg group, located at the edge of the Totes Gebirge, benefits from frequent cloud accumulation, resulting in above-average precipitation in that area.

In the summer half-year, a distinct thermocline forms, and only the surface layer warms up, in autumn mixing occurs again, followed by ice formation.

Due to the discharge of untreated wastewater, a eutrophication trend could be detected in the years 1963 to 1973 and the oxygen saturation above ground was already decreasing.

Several supply and disposal pipes run through the lake, connecting the rest areas at the Seewiese and the beach café located on the southern shore to the sewage system.

The crustacean plankton in Lake Altaussee is largely composed of species such as Cyclops abyssorum, Eudiaptomus gracilis, Daphnia hyalina, and Eubosmina longispina.

However, centuries of prioritizing spruce as a fuel source for the salt flats have led to a significant depletion and displacement of fir and beech trees.

In the Seewiese, a treeless area created by mowing and grazing, there are tall perennials such as meadowsweet ( Filipendula ulmaria ), ring thistle ( Carduus personata ), and monkshood (Aconitum napellus ).

[17] With its largely undeveloped shores with nearby marshes and wooded steep slopes, the lake provides habitats for many animal and plant species and the area has been under nature protection since 1959.

[18] The Walter Munk Foundation for the Oceans supports research projects in the field of limnology, ecology, and underwater archaeology at Lake Altaussee.

Together with the University of Natural Resources and Applied Life Sciences Vienna, a high-resolution multibeam echo sounder was used to create a detailed 3D model of the lake bottom in 2019.

It shows, among other things, sediment formations of various kinds, large boulders, crater-shaped underwater springs, and around 100 standing tree trunks with heights of one to about fifteen meters distributed over the entire lake.

The char in Lake Altaussee spawn from October to November on gravel banks that are free of silt, typically at a depth of around 20 meters.

[22] The perch (Perca fluviatilis) was not originally native to the lake but entered the water body at the end of the 1980s for yet unexplained reasons.

As a foreign fish species, it changed the aquatic ecosystem and caused damage to the population of minnows and Arctic char, on whose spawn it feeds.

It contains a small natural history museum on the second floor, which focuses on Lake Altaussee and the numerous fossils found in the region.

During the Daffodil Festival at the end of May/beginning of June, which lasts several days, a boat parade takes place every third year on Lake Altaussee.

Subsequent to the catastrophic floods of 1897 and 1899, the remaining traces of the rake were eliminated as part of the shore reinforcement measures.

Today, this consists only of fragments scattered over an area of about 20 × 40 m. As the nobility began to settle in Ausseerland, Altaussee also attracted more and more writers, painters, and musicians.

Raoul Auernheimer, in his autobiography "Das Wirtshaus zur verlorenen Zeit", compares the lake to an inkwell into which “the poets sitting around in circles dipped their quills”.