For many decades the CTC had been running a pothole reporting system using pre-printed postcards. With the advent of online mapping, it became possible to report hazard locations via a website.
Fill That Hole was originally a small part of the large CTC Maps website project. But it soon became very popular with cyclists and other road users, and is now heavily used.
The site was shut down after 17 years when the service was moved to be handled by MySociety's FixMyStreet website.