GT Reef is one of the sites McFadyen and his club found along the Kurnell cliffs between Cape Solander and Cape Baily, a stretch he has dived only around 15 times in more than 2,400 Sydney dives over twelve years – which says more about Sydney divers' habits than the quality of the diving. The name was short for Golf Tee Reef, after a Bureau of Meteorology radar dome on the headland that looked like a golf ball sitting on a tee; the structure was knocked down in late 2025, so the name is now a piece of local history rather than a navigation aid. The reef is a series of small walls, one running east–west and the others roughly north–south, rising from about 25 m where boats run in from deeper water to a shallower section of around 10 m where most divers anchor.

The walls are not high but create ledges and small overhangs for fish and invertebrates. Sponge life is not prolific compared with the richer sites to the north, but there are attractive sea squirts, and fish life includes bream, several species of leatherjackets, silver sweep, yellowtail and others typical of the Kurnell coast. The site has plenty of room for exploration and McFadyen describes it as a nice dive that needs more exploring.

Because it is mostly shallow, it suits Open Water divers with some boat experience and is a practical second dive after a deeper site such as the Whale Watching Platform or Tabbagai Point. As with the whole Kurnell coast, there is no regular charter, so it is a private-boat or club dive; boats can come from either Botany Bay or Port Hacking.

Boat only – the Kurnell cliffs are sheer and in Kamay Botany Bay National Park, with no practical shore entry. From Botany Bay, launch at Kyeemagh (Cooks River), Foreshore Road or Bonna Point (Silver Beach, Kurnell), run out past Captain Cook's Landing Place, Inscription Point and The Leap, then turn south along the cliffs; from Port Hacking (Gunnamatta Bay/Tonkin Park or Lilli Pilli ramps) run out past Bass and Flinders Point and north-east along Bate Bay past Cronulla Beach and Cape Baily. It is 15–20 minutes from either Botany Bay or Port Hacking.

McFadyen's GPS is 34° 01.3884' S 151° 13.9190' E; the old transit lines the western end of Congwong Beach at La Perouse with Cape Solander, just north of the vertical cliff face to the west. The 'golf tee' radar dome that gave the reef its name was demolished in late 2025, so use GPS. Run in from 25 m and anchor in the shallower section at about 10 m.

The Kurnell cliffs face east to south-east, so they catch north-east, east and south-east swell; plan on seas under about 1.5 m. Being close to the Botany Bay entrance, visibility drops on the ebb when dirty bay water flows out, especially after rain – dive on a high or incoming tide. South of Cape Solander the coast is more exposed to southerly and south-easterly swell as well, which makes the shallow 10 m anchorage surgy.

Choose a day of small seas and light westerly or northerly winds. The bay-mouth effect on visibility is smaller here than at The Leap but still noticeable on a big ebb after rain. Morning dives avoid the summer north-east sea breeze.

From the anchor at about 10 m, follow the east–west wall to the east until it meets the north–south walls, then work along these in 12–20 m before returning to the anchor along the shallower reef. The site is largely unexplored – note features for next time.

No regular charter – private boat or dive-club (St George Scuba Club) only