Location: IP3 8UH, United Kingdom
This was an epic course put on by Steve Grimwood and the Elmy Cycles crew (with a little help from some cycling buddies). It featured two fairly long sections of road, lots of twisting grass track, and the extremely fun/challenging 4x4 section.
My youngest son Michael (7) raced on a lightweight BMX bike, and was probably the fastest out of all the riders up the 7-step climb. Here's a video of parts of the race, with a bit of Iceni Velo bias: