Geo-Route (Rorschach – Weinfelden)

And where do the scattered boulders of different rocks in the landscape come from? The answer leads to glaciers, rivers, and even the seabed.

Starting in Rorschach, you soon reach the Goldach delta on the Geo-Route. This typically shows how pebbles that have "travelled" from the (pre-)Alps are deposited. And it is astonishing that the entire lake basin will be filled this way in 15,000 years. Next, the route continues via Hagenwil and Zihlschalcht to Sulgen. Along the way, you learn that today's wine is owed to Ice Age glaciers and that the rugged Holenstein was also formed by an Ice Age river.

After Sulgen, the route connects to the Thur River. Above the Thur bridge at Bürglen, you see rock slabs in the riverbed made of rocks originating from the Central Alps – deposited by an ancestor of the Alpine Rhine when the Alpstein was still beneath the earth's surface. Always following the course of the Thur, you finally reach Weinfelden.