I moved to the city of Brotherly Love almost 5 years ago, and say what you will about Philly (some good, some bad...), but one thing I love about it is the ever-expanding bike route system.

Check out this interactive map that shows you what trails/routes/lanes exist, and which ones are being planned and/or built. In the 5 years I've been here the map has just about doubled in showing available routes.

http://connectthecircuit.org/

Seriously, I can lose about 45-60 minutes nosing around this map.