Answer:
The largest lake in Central Europe is Lake Balaton
Assuming this involves another form of shifting tectonic plates, the answer would be earthquakes. Another form of the question is asking for continental drift.
When rock from the mantle melts, moves to the surface through the crust, and releases pent-up gases, volcanoes erupt. Extremely high temperature and pressure cause the rock to melt and become liquid rock or magma. When a large body of magma has formed, it rises thorugh the denser rock layers toward Earth's surface
Well when Water or rain doesn't fall to replenish the old water the sun keeps evaporating more and more water until there is known left like in California a couple years back or the desert