We had a similar experience on our first trip to Yellowstone in the mid 70's. We were tent camping and looked over the maps one night, found this road that looped behind a mountain, Bunsen Peak, to a waterfall and decided to take it the next day. As I recall, about a half hour in the switchbacks started, they weren't on the map
. No place to turn around, so forward, backward several times for each turn while getting expert advice from my hysterical wife. We got to the waterfall, Osprey Falls, had a Lynx run in front of the car, BTW we were driving a 1972 Monte Carlo and saw some great scenery. Came out the other end unscathed. The road/trail/path exited into the NPS employee site and we got the strangest looks, one guy pulled us over and asked where we came from, so I told him NJ
Shook his head and told us the road was an old Jeep trail, which we had found out. On a later trip we walked what we had driven; there were now signs saying no vehicles; I guess others had done the same thing.
Sometime, just sometimes, doing stupid stuff makes for good memories. But just sometimes.