Api 1991

Two members of the 1990 expedition returned to Mulu in 1991 and with the assistance of Park Guides put together a small caving team.

400m of new passage were explored in Simon's Cave and several surveying queries were tied up in the area. Two new caves were also entered and partially explored: Palm Cave high on the side of souther Gunung Api and visible from batu Bungang as the top of a high white cliff was only entered once. 165m were surveyed and a further 300-400m explored, mostly large ramp type passage. Fern Rock Cave 30m above the river level in the Deer Cave massif had previously been partially explored by National Park guides. The expedition surveyed a further 845m of mostly small passage breaking into a large, horizontal southward trending passage.

Both Palm Cave and Fern Rock Cave were left wide open with many leads.