Murra-El-Elevyn is widely described as a magnificent recreational cave dive – by Nullarbor standards. The CDAA describes a 300 m long main tunnel with two interconnected phreatic networks, one passage half-filled with water and another completely submerged, with a large rock formation marking the division between passages. Visiting writers note massive creamy-grey rock formations, depths around 20 m and a silt area where care is needed.

The cave was explored in 1976 during the early South Australian expeditions to the Nullarbor. Today it is dual-rated by the CDAA: the section from the entrance lake to the main chamber is Cave-rated, while the North-West passage (beyond a 60 m line) and related routes including 'Gary's Back Passage' are Advanced Cave, with interesting sidemount passages.

Because it is shorter and shallower than Cocklebiddy or Weebubbie and has a more manageable entry, Murra-El-Elevyn is often the first Nullarbor cave dived by visiting teams. It is still remote, permit-controlled and serious: divers must apply in writing to DBCA at Esperance at least four weeks in advance.

Teams usually combine Murra-El-Elevyn with Cocklebiddy and Tommy Grahams on a single trip based at Cocklebiddy Roadhouse, since all three are within a short drive. The water is brackish groundwater at about 19°C, so a drysuit or thick wetsuit is needed for long dives, and good trim is essential to avoid stirring silt in the smaller passages. Lines should be checked on each visit because shifting boulders and past expeditions have left old line in places.

The Nullarbor caves lie along the Eyre Highway between Norseman and the SA border, roughly 11-14 hours' drive from Perth. Cocklebiddy Roadhouse (fuel, meals, water, showers) is the base for the central caves; Norseman, 435 km west, is the nearest regional centre. Access to the cave entrances is by unsealed station/bush tracks (4WD recommended), and all cylinders, compressors, gas, water and rope/hauling gear must be carried in.

Murra-El-Elevyn is reached by track from the Cocklebiddy area. Divers carry equipment from the doline to the entrance lake. DBCA written permission is required.

Surface weather matters mainly for access and safety: summer temperatures can exceed 45°C, making gear hauls dangerous, while winter nights are cold. Heavy rain is rare but can flood entrances and destabilise rockpiles (the 1988 Pannikin Plains collapse followed a severe storm). Underwater conditions are stable year-round: groundwater at about 19°C (24°C at Tommy Grahams), often brackish to saline with haloclines, and visibility commonly 20-50 m or more unless disturbed.

Autumn to spring (April-October) is the usual expedition season. Silt in some passages can reduce visibility quickly if disturbed.

Cave-rated divers dive from the entrance lake to the main chamber on the line. Advanced Cave divers may enter the North-West passage (60 m line) and related routes such as 'Gary's Back Passage', including sidemount-restricted sections.

CDAA dual-rated: Cave (entrance lake to main chamber), Advanced Cave (NW passage beyond 60 m line, Gary's Back Passage). Sidemount useful in advanced passages. DBCA Esperance permit, four weeks' notice.

No operator – CDAA-rated divers by permission only.