I had visited this trail before the pandemic for the simple reason that it traversed the steepest terrain I could find on my topo map. See Iron Mountain Park
Sunday, September 5, 2021
45.4157944, -122.7026583
google map 
45.4162556, -122.6986611
45.4177361, -122.6965028
45.41795, -122.6918028
I had intended to ride the switchback down the face to unfamiliar trails below. The hairpin turns look impassible. So following the posted advice, I took the familiar path to exit by the golf course.
The discovery of iron deposits near Oswego in 1861 excited hopes that Oregon could supply most of the demand for iron on the Pacific Coast. Oswego also had timber for charcoal fuel, a river landing on the Willamette, and waterpower from the outflow of Sucker Lake now Oswego Lake. post