Find leisure cycling routes

Check out Sustrans National Cycle Network for inspiration on leisure cycling routes.  This site provides a UK-wide network of signed paths and routes for walking cycling, wheeling and exploring outdoors.   

I like this site as it's easy to filter on routes by region, distance and whether they're traffic-free.  It also gives route ideas along with a bit of a description, the distance, how long it's likely to take and the type of ground it covers which helps with planning.