The Japanese Antarctic Research Expedition carried out the reconnaissance survey of the Sør Rondane Mountains (72°S, 25°E) in February 1984. The reconnaissance party consisted of a four-man snowmobile party and a six-man snow vehicle party. The latter party left the Icebreaker SHIRASE in Breid Bay by helicopters on February 7th. Two SM40S-type snow vehicles were knocked down on board, transported by helicopters and set up at about 11km inland from the head of Glacier Bay (provisionally named "L0" point). The snowmobile party was transported 55km inland from the coast ("30 miles point") and started towards the Romnoesfjellet. They arrived at the "Seal" rock on February 11th. The snow vehicle party arrived there on February 13th, after building the prefabricated hut at the "30 miles point" and setting snow stakes along the route from the "L0" point to the Romnoesfjellet via the "30 miles point". During 9 days survey on the northern flank of the Sør Rondane Mountains, they set two geodetic control stations using the JMR satellite positioning system, and carried out geological investigation and collection of rock specimens for the paleomagnetic study. In addition, they conducted the search for the base camp site for the coming season. Both parties were picked up by helicopters at the "30 miles point" on February 23rd after depositing the snow vehicles and other materials.