The karst plateau of the Stony Sea is a National Park on the German side and a nature reserve on the Austrian side. The mountain region is designated as a UNESCO Biosphere Reserve Protection. Because the weather is unpredictable we settle for a short hike up to the Ingolstädter hut and the Riemann protection house. We arrive at the Kaltbrunn Alm, go to the Dießbach reservoir and continue to the Ingolstädter house. The Dießbach reservoir is at 1415 meters, from there to the cabin it is a altitude difference of more than 700 meters. The first three hundred meters we walk through coniferous and pine forest and on narrow strips of alpine meadows. The gray-white rocks and the sparse soil indicate that we walk on limestone rock. The area of the Stony Sea belongs to the northern limestone Alps. The limestone formed in the passive continental margins of the Tethys ocean, the Tethys ocean split the supercontinent Pangaea since the Triassic. When the African plate began moving towards the European, the limestone deposits were squeezed, pushed over each other and folded. When we arrive at the Ingolstädter hut we have reached the karst plateau. Snowfields in August show that we are 2000 meters high. The karst plateau is a largely vegetation-free rock desert. It covers an area of about 150 square kilometers. Fischer describes the geomorphology as a relief of the type low mountain range dominated by mountains with the character of gate posts. These include near the Ingolstädter hut the große Hundstod and the Schindkopf. The repeated glaciation of the mountains during the Pleistocene has contributed significantly to the morphogenesis of the stone sea. Abrasion by glaciers and corrie formation have formed the plateau. As is common in highly karstified areas, there are no flowing waters. The landscape is dominated by flat valleys or troughs, which are littered with rocks of different sizes. After a long hike across the plateau we reach the Riemann house just before sunset. It is dominated by the Sommerstein that is also often used as a climbing wall. The next morning the valley of Saalach and Urslau is under a dense cloud cover. But above the stone sea there is bright sunshine. While my companions climb the Sommerstein I walk towards the center of the plateau, ion the direction of the Kärlinger house. Unfortunately there is not enough time to reach it. Kärlinger house, Funtensee and Königssee have to wait for another time. The Stone Sea is worth a second visit.