Today I have a suggestion for these who like to spend their holiday around Vienna and have an additional 2 hours of free time to fill.

In the Hinterbrühl mine gypsum was tapped starting from 1848. However, in 1912, as the result of an explosion, the lower levels of the mine were flooded and the work had to stop. The many litres of crystal clean water in dark corridors tempted people to visit the mine, so the Austrians created a path for tourists in 1932. Thanks to this we may admire this charming place.

Convenient placement and perfect protection against bombs meant that during the second World War the Nazis took over the mine, pumped out the water and transformed this tourist attraction into an underground plant producing parts for Heinkel He 162 warplanes. To make the plant more useful, they painted its whole interior white and concreted the bottom of the drained lake.

After the war the grotto was flooded anew and again made available for tourism. Despite the devastating actions of the Nazis, the mine together with its underground 6200 m2 lake is still a uniquely beautiful place and one of the most well-known underground tourist paths in Austria.

We started the trip inside the grotto by putting on warm blouses and sweaters, as, similar to other caves, the inside temperature does not exceed 12 C. At the beginning we wandered down a long passage to finally reach the bigger chambers, where we could see expositions connected to gypsum mining, miners' work and the production of warplane parts. Every step I marvelled more and more, looking at the colour and the structure of the walls. They are so soft that we can scratch them with our nails to reveal many different colours, starting from pewter and ending with white. The picturesqueness of this underground nook has been recognized not only by tourists but by film producers as well. The pictures for the "Three Musketeers" were shot on the underground lake, and parts of the scenography and the boat from the movie can still be seen here. Our trip ended on the lake's bank. Here we found quiet, electric flat-bottom boats. We punted almost soundlessly between the dark chambers of the caves. The lake was as flat as a table. Apart from the quiet music composed especially for the mine and drops dripping we could hear nothing else. The lake has fabulous underwater illuminations in a few places, which gives it an even more unique atmosphere.

To recognise the charm of this underground lake you have to see it for yourself. It is a pity that the boat trip on the lake takes only 15 minutes. With pleasure I would stay there much longer.

I do recommend it!