Harold Pinchbeck watch in Mont Blanc

The account of 'Will Battle' on the Ultra-Trail du Mont Blanc

It is 6.30pm on a balmy late-summer evening in Chamonix in the French Alps.  Along with 2300 other competitors I stand on the start line of the Ultra Trail du Mont Blanc.  Before us lie 166km (103 miles) of running and walking, and a net climb and descent of 9500m.