Suburban walking peters out into an undulating ramble largely following the Vanguard Way to the North Downs, then more undulations back through Marden Park to Caterham, Happy Valley and Farthing Down before descending to the finish at Coulsdon South. If the undulations get too much (there is around 2,000ft/600m of ascent during the day), there is a breakpoints at Caterrham station (14 miles; in zone 6, bus routes also available once we get there)