When I lived in another place, it was a 10 mile ride around town. There were several routes you could take from table flat up to 'gentle' rollers. The ride was through a bunch of neighborhoods and included the town square. The people there were super cool and patient about bike riders, and aside from that the town wide speed limit was never above 35. I totally miss living there is nothing else for that aspect.
Where I live now, the best and easiest places to ride are a local park with a walking/biking trail and the golf cart paths in Peachtree City. I do it far less than I should simply due to the load up the truck and go aspect.