This is the bonus/final cache for the Adventure Lab "Kinnekulle Adventure".
To solve this mystery, you need to complete the Adventure using the app "Adventure Lab" on your smartphone. You can click on the following link to access it:
https://labs.geocaching.com/goto/KinnekulleAdventure
After solving each step, you will get clues to find the proper coordinates:
N58 34.ABC E013 23.BDE