Lake Constance is the second largest freshwater lake in Central Europe at 40 miles long and 8.5 miles wide (second only to Lake Geneva), and is located between between Germany, Switzerland and Austria. Formed by glaciers during the ice age, the lake is fed by the Rhine River as it flows out of the Alps into the southeast part of the lake. South of the lake are the Alps, and north of the lake are the hills of Germany.
Over time the shores have become increasingly crowded, and growth has caused increased concerns of pollution. The increase of boat traffic on the lake has increased these concerns. But in recent years, there have been agreements between the surrounding countries to protect the lake and its habitats, and lately there have been renewed efforts.