Route: Billingeleden (Sweden)

https://www.vastsverige.com/skovde/leder/ledsida_billingeleden/

The Billing Trail is an approximately 57 kilometer loop hiking trail that takes you around the whole of Billingen mountain. It runs along the edge of the mountain with fantastic views, down on the slopes through pastures and forests and on the flower-rich limestone plateau in Berg.

Note that previously the trail officially included a 10 km (each way) out & back section to Simsjön, for a total of 77 km.  The pdf map linked at the above website still shows this as part of the trail (as of July 2020), but a local official confirms that the "official" route is now just the 57 km loop.