We began at 7,000 feet above sea level on a breathtakingly scenic spur of the Great Rift Valley. We hauled ourselves up lung-bursting climbs but every time we rounded a bend, there was yet more uphill to climb. Lungs cried out for oxygen in the thin air and my thighs felt like hot metal ingots. Some hills were too steep to cycle so we resorted to pushing our bikes.

After an unrelenting five kilometer stretch, I saw the bike rack by the side of the road. Whooping with joy, I turned into the layby in third spot. It had taken one hour and 40 minutes to cover 27 kilometers and ascend to 9,000 feet above sea level...and this was only lunch. It took 40 minutes for the tail to arrive and, collectively, we were a sorry sight, cursing and collapsing in a mixture of exhaustion and ecstasy.

After lunch, we spiraled down 4000 feet over the next 30 kilometers around sidewinder bends - those with speedometers registered 49mph. After 60km we stopped at a river crossing where we flopped into the icy waters - a few Kenyan washerwomen giggled at our horseplay.

A few of us slipstreamed each other to minimize the effort of the final 20 km. An electrical storm unleashed a violent downpour which was initially rejuvenating but after a while debilitating.

After four hours and 27 minutes of cycling, we cruised over the equator again. However, the trip on someone's speedometer showed only 99km so we pushed 500 meters further, hung a U-turn and crossed the equator for the third time to rack up the 100-kilometer target!