During melting of the glacier, Wehntal, the lower Glatttal and Furttal valleys filled about 180,000 to 150,000 years ago with cold glacial lakes.

With the increasing warming period about 20,000 years ago, the glaciers melted away in stages to Zürich, later Hurden and formed the Seedamm at the Obersee lake area respectively the Ufenau, Lützelau and Heilig Hüsli islands on Zürichsee, and finally retreated into the alpine mountains.

[1][2] In 1890 the most important site of Ice Age animals in Switzerland was discovered in Niederweningen: 100 bones, molar teeth and tusks of at least 7 different individuals of mammoths, including a very young calf, were found in a peat horizon at the base of a gravel pit.

[5] Various exhibits range from the colonization in historical times to the flora and fauna of the Ice Age, and further back to the living resources of the tropical Jura sea.

Other fossil finds date back to other glacial animals, such as woolly rhinoceros, wild horse, steppe bison, wolf and cave hyena.