Following the Palmer, Buckskin loop and adding in the walk from the main parking lot.  Expect at least 5.5 moderate miles
This loop trail takes you on a walk around the main section of the formations that constitute the Garden of the Gods.

Parking at the large parking lot: https://maps.app.goo.gl/Xcf1tnnCqxvcKjut7 - for Google Maps

https://www.alltrails.com/trail/us/colorado/palmer-buckskin-charley-niobrara-and-bretag-trail-loop