Lake Almindsø near Silkeborg is one of Denmark’s cleanest lakes. There is no agriculture nearby or polluting drainage into the lake and it is a popular bathing lake with two large pools, Østre and Vestre (east and west), and several smaller bathing spots – including the beach at Aggerholm that was laid by German soldiers stationed at the nearby German military headquarters at Silkeborg Bad during the Second World War. The area boasts interesting flora and fauna including 20 species of underwater plants and 450 species of aquatic animals. On the south side of the lake, there are high slopes with ochre-rich springs at their base and the two tributaries Skade Bæk and Odder Bæk. However, most of the water supply comes from the groundwater seeping up through the bed of the lake. A depth of up 20 m makes Almindsø one of the deepest lakes in the River Gudenå system. It is approximately 4 km around the lake, and a very beautiful walk, including the Kroghs Bænk viewpoint.