Secret Street / Area “Garden of Gods”. If you are on the road in Colorado Springs towards the NAMIQ gold mine, then you can drive into a large park in the marked area.
It seems to be a popular destination in town. Is done really nicely, just no achievement for it.
Note: Of course you need the DLC “Colorado”!
Route to Area “Garden of Gods”
- Drive down I25 to the city of Colorado Springs
- Leave I25 to mines of “NAMIQ”
- Note: “Einfahrt” means entry on the picture below