First stage is virtual. You will need to do a short field puzzle based on items at this location that weren't placed by the CO. Put the answer in the checker at the link below to receive the final coordinates close by. You do not need to go in the location, just make observations from the outside.
The puzzle:
5-3-1
9-2-2
7-4-2
10-1-1
1-3-1
You can validate your puzzle solution with certitude.