Some friends who occasionally cycle ask wanted to enjoy a ride on a trail, away from cars that was scenic and on the easier end of the spectrum. I recommended to 10B Fire trail in Dharawal National Park. A mostly flat and quite ride out and back as far as you like.
I have just acquired a Surly Pugsley Special Ops (a fat bike for those otherwise unfamiliar), after being interested in them for a few years. Being back in Oz, they are about as — perhaps even less — common as snow on the beach. It was for riding on the latter where my interest primary sat.