During a sea voyage in the area with brother George in HMS Pioneer in 1909, Dennistoun had identified what he thought was a possible route but as he was not able to reconnoitre it he instead decided to take a route recommended by Donald Sutherland. After rowing across in a boat to the mouth of Sinbad Gully at the base of the peak they starting climbing at 7.30am on 13 March 1911. Dennistoun and Beaglehole climbed via the south east-ridge through the bush until 300 metres short of the summit Beaglehole decided it was too difficult to continue and stopped. Dennistoun continued on alone up steep, smooth slabs of granite, to reach the summit at 1.15pm.