Hidden Nu I larbo

摘要

ALMOST EXACTLY 100KM west of theWestern Australia-South Australia border, Graham Pilkington twists and clambers down a fissure little wider than his body into one of the first of Old Homestead Cave system's large passages. Light from his head-torch pierces the blackness as his hands grip a wet ladder made slippery by condensation in 90 per cent humidity, before his boots thump to the cave floor, raising a dull echo.This low, wide entry passage sits below the Nullarbor Plain, the world's largest limestone karst landscape, which is tens of millions of years old. The Nullarbor - a dry, flat, 200,000sq.km savannah -stretches 1100km along the southern coast of Australiafrom Balladonia east of Norseman, WA, to north of Yalata in SA. Above ground it is famously featureless. Edward John Eyre, the first European to cross the Nullarbor in 1840-1841, described it as the "sort of place one gets into in bad dreams". But beneath the surface is a complex world of tunnels within a vast slab of limestone. Much of southern Australia is also riddled with smaller blocks of limestone.