Middle Ground North is the smaller companion to Middle Ground, lying straight out of Port Hacking in line with Oak Park. It is compact and elongated, running north-west to south-east, with the surrounding sand at 31–32 m rising to a reef top of about 28–29 m. The eastern wall, particularly at its northern end, stands two to three metres high with small overhangs; the western wall is lower but has similar overhangs, and near the northern end an inlet cuts into the reef with larger boulders on top.

A large crack runs north across the reef, giving a natural route back to the east side. What makes the site special is the growth on the reef top. Sea whips are abundant, and many host tiger anemones – some carry up to half a dozen – which McFadyen notes is rare for southern Sydney.

Gorgonians, sea tulips and sponges add colour, eastern blue devilfish and pineapplefish shelter under the ledges, and huge numbers of yellowtail and seapike school above, with kingfish passing occasionally. In February 2025 he also recorded silver sweep, small leatherjackets and red morwong, with at least 12 m visibility. Because the reef is small, anchoring directly on it is difficult; boats drop on the sand and drift back.

With no charter operating from Port Hacking, the site is dived mainly by the St George Scuba Club, which does most of the diving south of Botany Bay. At 28–32 m, no-deco time on air is short, so it suits deep-experienced divers on nitrox who enjoy compact reefs with unusual invertebrates.

Boat only. Launch in Port Hacking at Tonkin Park/Gunnamatta Bay (Cronulla), Lilli Pilli or Grays Point and run out past Bass and Flinders Point and Oak Park into Bate Bay. Head straight out of Port Hacking in a direct line with Oak Park – about 10 minutes.

McFadyen's GPS is 34° 04.301' S 151° 11.526' E. The reef is small, so anchor on the surrounding sand and drift back onto it; if the edge is not visible on descent, swim perpendicular to the reef's NW–SE axis and it should appear within 20 m.

Bate Bay faces south-east and is open to swell from the east through to the south; southerly and south-easterly seas over about 1.5 m make the Bate Bay reefs rough and the Port Hacking bar can be dangerous in big swell. North-westerly and westerly winds give the calmest conditions; summer north-east sea breezes chop up the bay in the afternoon. After heavy rain, Port Hacking and the Cronulla stormwater drains discolour the inshore water.

Current and wind vary and affect how the boat lies over such a small reef; plan for light conditions. Visibility of 12 m or more is normal on clean ocean water, lower after rain.

Go north along the eastern side exploring the overhangs, cross the reef top at the northern end (inlet and big boulders) heading west, follow the western edge about 50 m south-east, then follow the large north-running crack back towards the eastern side (about 25 m) and the anchor.

Nitrox recommended.

No regular charter – private boat or dive-club (St George Scuba Club) only; no charter boat currently operates out of Port Hacking.