The Southern Ledges are described by marine life writers as among the most exciting dive sites at Lady Musgrave. They lie on the drop-off along the south side of the reef, where the wall is undercut by ledges and caves at 12-26 m, and they offer a more rugged, exposed experience than the lagoon and western bommies. The ledges and undercuts shelter wobbegong sharks, crayfish and lionfish, stingrays rest on the sand at their base, and turtles move along the wall.

The wall itself carries black coral trees, gorgonian fans, sea whips and spiky soft corals, and reef sharks, eagle rays and manta rays pass in the blue. Because the south side faces the prevailing south-easterly trade winds, the site is dived only in calm conditions, which means it is less often visited than the sheltered sites. When conditions allow, the combination of wall, ledges and invertebrate growth makes it a standout.

The depth and exposure make it most suitable for divers with Advanced certification and good buoyancy. A torch helps in the undercuts, where the colours of soft corals and sponges are otherwise lost. Current operator listings use a different set of names for their outer-reef drifts (for example The Caves and Jeff's Edge, both walls with overhangs), and the Southern Ledges may overlap with one of these; divers should ask the operator which site is scheduled.

Private boat owners anchored in the lagoon sometimes dive the south side from a tender on calm mornings, but should carry an SMB and have a surface cover because of the swell and current.

Lady Musgrave Island is about 96 km north-east of Bundaberg and 59 km east of the Town of 1770. Lady Musgrave Experience departs 15-17 Marina Drive, Burnett Heads (15 minutes' drive from Bundaberg; parking at the marina) at about 7:30 am for a roughly 2-hour crossing to its pontoon in the lagoon; 1770 Reef Eco Tours leaves the 1770 Marina (free parking beside the marina cafe) for a roughly 90-minute run. Private vessels anchor inside the lagoon via the marked entrance channel through the reef.

The Southern Ledges are on the exposed southern drop-off of Lady Musgrave Reef, reached by tender from the lagoon or by private boat in calm conditions.

The lagoon itself is diveable in almost any weather, but the crossing is open ocean and tours are cancelled when south-easterly trade winds exceed about 25 knots or the swell is over 2.5 m. Outer-reef drift sites are chosen by wind and tide: the northern and western edges shelter from south-easterlies, the southern ledges need light winds or northerlies. Currents strengthen on spring tides and the outer sites are run as drifts on either the flood or ebb.

Cyclone season is November-April; summer storms and plankton reduce visibility. Calmest seas are often September-November and March-April. The south side faces directly into the prevailing south-easterly trades and swell, so it is dived only in calm spells or northerly winds.

Descend onto the lip of the drop-off at 12 m, drop to the ledges at 18-25 m and follow the wall, looking under the undercuts for wobbegongs and crays. Turn with plenty of margin, ascend along the wall and finish the safety stop on the reef edge.

Lady Musgrave Experience runs daily tours from Burnett Heads (Bundaberg) aboard Reef Empress to its Lady Musgrave HQ pontoon, with certified divers transferring to the dive tender Underworld for the 'Adventure Outer Reef Double Dive'; overnight stays on the pontoon allow extra and night dives. 1770 Reef Eco Tours also dives Lady Musgrave from the Town of 1770. The southern drop-off is dived only when south-easterly conditions are light; private boats anchored in the lagoon also visit.