Fairfax Lookout is the easternmost of the North Head boat sites, lying under the clifftop viewing platforms of the same name at the point where the inner harbour face turns toward the open sea. Sydney Dive Charters lists it twice – once as a 10–30 m site of 'walls, boulders and small swim-throughs', and again as a deeper 26–33 m dive to 'colourful sponge gardens renowned for their colour and diversity of marine life' – which captures its two levels. The upper reef is the familiar North Head boulder slope with short walls and gaps between blocks; below about 24 m the reef steps down more steeply to sand at 30 m or more, and it is here, beyond most surge and light, that the sponge gardens reach their best.

Because this corner catches more water movement than the sheltered sites to the west, the growth is lush and the fish bigger. Kingfish and bonito patrol the outer edge in summer, schools of yellowtail and pomfret hang on the wall, bull rays and eagle rays cross the sand, and grey nurse sharks occasionally wander round from Bluefish. The deep faces carry gorgonians, sea whips and large sponges; the shallower boulders have the soft corals and sea tulips typical of the reserve, with weedy sea dragons on the sand line and wobbegongs and Port Jackson sharks under the ledges.

Depth makes it an Advanced dive, and the tidal current through the Heads is stronger here than anywhere on the inner face, so operators run it as a drift when the tide is running. Its position on the edge of the main shipping channel means ascents must be on the anchor line or a DSMB close to the cliff. Fairfax Lookout suits Advanced divers who want the deepest and richest of the North Head reefs without leaving the shelter of the Heads, and it completes the North Harbour Aquatic Reserve circuit.

Boat only. Dive Centre Manly loads at Manly Cove beach beside the wharf; Pro Dive Manly and Sydney Dive Charters load at the Little Manly boat ramp (end of Stuart Street, Manly – free parking, set-up benches, toilets at the reserve); Sydney Dive Charters also picks up at Rose Bay public wharf. From Manly the run is 10–15 minutes across North Harbour to the inside of North Head, 20–25 minutes from Rose Bay.

Private boats launch at Little Manly, Roseville Bridge (Middle Harbour, 30 minutes) or Rose Bay. Boats anchor on the reef in 15–20 m or run in toward the cliff and drop the anchor when the bottom appears; there are no moorings, and many abandoned anchors litter the reef. Fairfax Lookout is the last anchorage before the tip of North Head; skippers use the lookout platforms on the clifftop as the mark and anchor in 18–22 m below them.

The inner face of North Head is the most sheltered ocean-quality diving in Sydney. It faces west-south-west into the harbour, so it is protected from the north-east sea breeze and from northerly and easterly swell, and is at its best when a strong north-easter is blowing and every ocean site is rough. It is exposed to southerly swell rolling through the Heads: a big southerly (over 2 m) sends surge along the cliff and dirties the water, though the deeper sponge gardens are usually still diveable.

Tidal current runs along the wall, east on the flood and west on the ebb, strong enough to plan a drift; slack water is easiest for novices. Visibility is 10–15 m on average, 25 m on winter westerlies, and drops after heavy rain when the harbour flushes brown. Ferry, shipping and small-boat traffic through the Heads is constant – ascend on the anchor line or a DSMB close to the cliff.

Being at the very tip of the headland it feels more of the ocean swell and tidal flow than the sites further in.

Descend to the wall at 20 m. Drop over the edge to the sponge gardens at 26–30 m for the first ten minutes, then climb back to the boulders and small swim-throughs at 15–20 m and work along the wall with the tide before returning to the anchor. Safety stop on the line; strong DSMB discipline because of the shipping lane.

Sydney Dive Charters – regular Advanced double dives, listed both as a 10–30 m reef and as a 26–33 m sponge-garden dive; Dive Centre Manly and Pro Dive Manly on their North Head rotation.