A lovely natural sandstone escarpment pool lies close to Kakadu National Park.Here is the destination for resting after walking all day long.In the middle distance is the sandstone escarpment with its blanket of eucalypts and dramatic flashes of black- and honey-coloured rock. And as far as the eye can see are the plains of the enormous park stretching under a violently blue sky.Park authorities do not say it is safe to swim anywhere in the park, other than the 50-metre concrete pool in Jabiru. But at the beginning of each dry season,the rangers survey areas high on the escarpment.