This is the frozen lake in Zell Am See, which as you will notice has a number of people walking across it!
Once it is frozen and safe enough to walk across (I believe they actually drive across it first!), the local authorities mark out a path by planting a number of trees into the lake. They even mark out ice hockey pitches and place park benches midway.
I used an HDR process to help bring out the detail in the ice and also the snowfields.