Flat Rock is a small, easy shore dive on the southern arm of Bondi Beach, directly below the start of the Bondi-to-Bronte coastal walk. It is not a spectacular site but it rewards a calm day and is one of very few Eastern Suburbs shore dives you can do from Bondi itself. From the entry the bottom is large rocks and sand patches sloping gently east to a sand flat at about 8–10 m.

Five metres across the sand is a low reef, with a single large flat rock on its southern side that is covered in kelp and gives the site its name. The northern end of that reef breaks into a jumble of rocks with sand pockets between them forming small swim-throughs. Back towards shore the platform reef ends in a short vertical wall, and set into it are three caves that run five to ten metres back under the rock platform: the first two are short and dead-end, while the longer one runs parallel to the shore and nearly always shelters one or more wobbegongs.

One of the caves was reported to have partly collapsed in early 1999, so treat them as overhangs to look into rather than swim through. Life is typical inshore Sydney: moray eels and small cuttlefish in the cracks, snakeskin and crimson-banded wrasse, small blue groper, common stingarees on the sand, yellow-finned pomfret and bullseyes under the ledges, six-spined leatherjackets, red morwong and the occasional crayfish deep in the caves. Its practical value is as a shallow second dive, a night dive or a training dive for people staying in Bondi, and as a site that is diveable in small south-easterly swell when the north end of the beach is not.

Parking is the real difficulty.

Park at the end of Wilga Street or Notts Avenue, South Bondi (parking is very difficult – metered, and full by 8 am on weekends; the Bondi Pavilion car park is the fallback with a 400 m walk). Take the stairs down to the coastal walk and then down onto the rock platform; the entry is to the right of the foot of the Wilga Street stairs. Enter, snorkel due east 25–30 m to about 6 m of water and descend.

Exit at the same spot. The carry is short but the stairs are steep.

Needs a fairly calm sea: a slight south-easterly swell and otherwise flat conditions are the best case. Any real swell from the south or east breaks across the platform and surges through the caves, and the outer flat rock becomes a washing machine. North-easterly winds are fine.

Tide has little effect. Visibility follows the general Eastern Suburbs pattern – best after westerlies, poor for a few days after heavy rain or a southerly blow. Before July 1991 the Bondi sewage outfall made the site diveable only in perfect conditions; that constraint no longer applies.

Descend at 6 m and head east over rocks and sand patches about 50 m to the sand; a low reef sits 5 m across the sand with the big kelp-covered flat rock on its southern side. Work the northern boulders and small swim-throughs, follow the edge south past the overhangs, then turn west back to the vertical wall of the shore reef and the three caves (5–10 m deep, the long one usually holding wobbegongs). Return west 20 m to the platform.

No regular operator – dived independently and occasionally by Dive Centre Bondi groups.