A metric century on the road, on an unsuitable bike. I found an 85km route on Bikely and added a little to it to get it up to a round 100km. Darlington - Shildon - Sadberge - Neasham - Girsby - North Cowton - Darlington.
Hard going on 32:16 with big tyres.
Distance: 62 miles (100 km)
Climbing: 2889 ft (see here)
Surface: On-road (plus a couple of off-road detours)
Time: 5 hours 50 minutes
Weather: Cold and wet under-tyre
Bike: Inbred Singlespeed (32:16, with 2.1″ tyres)
Update: Height gain added (23/01/08)