Cliff Bar created their 2 mile challenge, based on the fact that 40% of US urban transport journies were of two mile or less. The average journey within Darlington is a similar distance. As part of the challenge, they allow users to enter their address into a map which will show the 2 mile radius around their house. The map is searchabe, so shops, pubs, parks and banks within easy cycling distance can easily be found.
My map shows pretty clearly just how bikeable Darlington is. Personally, I'd say everywhere within town is easily cycleable - my workplace is only just within the circle, but is easily reached in 15 minutes.