Ruins of Desert Cathay 282 - Caravan on march near dry river bed at end of ancient Keriya river delta. With great skill in navigation and dead reckoning Stein found the end of the river even though it had shifted by many miles from its location as seen by Sven Hedin. It was mid-winter, such a journey through the desert could only be attempted in winter. The river was sighted many miles away as a silver sliver of ice among the sand dunes.