Tour Divide Challenge
Yes, I know it's MTB, but it sounds like an amazing test of bike riding.
And it has British interest right now with James Olsen of Evans Cycles and the technical guy behind Hoy Bikes competing. He's in the top four at the moment, so fingers crossed for a great result.
You can track his progress via this link:
The Tour Divide challenge is simple: Race the rooftop of North America by mountain bike; travel self-supported along all 2,745 miles of Adventure Cycling Association's Great Divide Mountain Bike Route; keep moving and be moved; exist well outside one's comfort zone in tackling a cross-continent bikepacking odyssey; finish as fast as possible without cracking.
Speed may be substance when it comes to Divide racing, but a flexibile, sang-froid style is the best attack for the Route's multiple personalities. Divide racing format requires no designated rest periods or set distances a racer must travel daily. The clock runs non-stop. She and he who can ride the fastest while making fewer, shorter stops usually hold the course records. With an average time-to-completion of three weeks in the saddle, Tour Divide is the longest–arguably most challenging–mountain bike time trial on the planet. It is a challenge for the ultra-fit, but only if ultra-prepared for myriad contingencies of backcountry biking.