A big pat on the back for me. I completed the metric century challenge this year!
You must ride one metric century (100 km, 62.18 miles) in every month to successfully complete the full challenge. Only single continuous rides of at least 100km qualify, not a daily or weekly total of several shorter rides that exceed 100km. Tea stops are allowed, nay encouraged.
I rode over 20 metric centuries throughout this year, with the Prudential Ride 100 counting as two because I rode from my hotel in Gants Hill to the start, did the 102 miles to the finish and then cycled back to Gants Hill to collect my car.