Baslerweiher

Baslerweiher is actually artificially created. In the 19th century, the Kleinsee was created as a drinking water reservoir for the city of Basel, 20 kilometers away (and financed by the city, hence the name). It was only in 2008 that the Baslerweiher passed into the possession of the canton of Solothurn and immediately became the largest lake in the canton - knowing some historical facts absolutely does no harm when biking through a beautiful landscape.
Actually a bit grotesque, in the front of the Seetel you blew up the dam to drain the lake and further back you build an artificial lake / pond - even if this is probably a bit different in time.

Dreamlike pond in a dreamlike landscape

It's nice there. Actually a good route to Nordic walking from Pony Ranch