Flowing down from Mount Everest, the river is believed to be the highest navigable whitewater. As such, it came to attention of teams participating in the world cup since Austrian paddlers made a world record descending from 3200 m altitude in France. Czechoslovak sportsmen then agreed to take up the challenge. A team of sixteen men, fourteen Czechs and two Slovaks, had been gathered and on 4 January 1973 they set on the journey from Děhylov by cars (notably using customized Tatra 138 that had to survive over 30,000 km forth and back). For the last part from Lukla to Pheriche, 110 porters were hired to carry the boats and other equipment. The actual river trip began on 1 April near Pheriche at 4243 mamsl and ran for 126 km down to Sun Kosi. The paddlers used both covered tandem canoes (C2) of Vertex brand and solo kayaks (K1), all made of fiberglass. The expedition returned home safely in August the same year.