The seaward side of Cape Banks, the northern head of Botany Bay, hides what McFadyen calls the equal of any dive site he has visited in Sydney – the Cape Banks Caverns. Just 50 m south of the tip of the headland the reef breaks into gullies, holes and caves 'galore'. Some of the gullies are more than 30 m long and 10 m wide with floors 10 m below their rims; walls drop from 5 to 13 m and from 13 to 20 m and more; and there are over six distinct cave systems plus numerous swim-throughs and overhangs, mostly south of the anchorage.

Offshore the reef continues out towards 30 m. The gullies funnel fish: yellowtail, sweep and one-spot pullers pour through them, bream, luderick and eastern rock blackfish hold near the rocks, eastern blue devilfish sit in the caves, and in winter Port Jackson sharks pile up in groups of up to twenty. Weedy seadragons live in the deeper kelp.

The wreck of the collier SS Minmi, which ran onto the cape in May 1937, lies scattered around the point and into Cruwee Cove on the bay side, and its coal turns up throughout the Minmi Trench a few hundred metres west. Cruwee Cove itself – also called Pussycat Bay – is the sheltered inlet just inside the heads on the northern side, a shallow 15 m maximum dive over sponge and kelp gardens with groper, morays, cuttlefish, red morwong and wobbegongs, sitting within a University of Sydney scientific control area and reachable from shore only by a long walk across the national park. Cape Banks itself is exposed and needs a flat sea, but on the right day it is a superb intermediate boat dive fifteen minutes from the ramps, and the sheer number of caves means several dives are needed to see it all.

Boat only in practice. Leave Botany Bay through the heads and swing round to the southern/seaward side of Cape Banks; anchor at the GPS mark or when the sounder shows 15 m, and start the dive in 12–13 m. About 10–15 minutes from the Kyeemagh or Foreshore Road ramps.

The headland is inside Kamay Botany Bay National Park with a 500 m+ walk from the NSW Golf Club/pistol club car park, so shore diving here is not realistic. No charter operator dives it regularly.

Cape Banks is the most exposed point on the Botany Bay entrance and takes the full force of southerly and easterly swell; the gullies and caves in 5–13 m are surge tubes in anything over about 1 m and calm seas are needed to dive close to the headland. Westerlies or light north-westerlies and a swell under 1 m are the conditions to wait for; in bigger seas stay on the 20 m+ outer reef. The bay's ebb tide can bring dirty water round the cape after rain – dive the flood.

Rock fishers are always on the cape and their lines are a constant hazard.

Anchor in 12–13 m and head south into the gully and cave system, following the walls from 5–13 m and 13–20 m and passing through the swim-throughs; there are more than six caves to find. Work back north along the deeper edge and finish in the 8–10 m gullies near the headland for the safety stop, listening for boats.

No regular charter – private boat or dive-club (St George Scuba Club) only; occasional Abyss or Sydney Dive Academy charter when conditions suit.