Middle Arch
Depth is the range from the top of the site to its usual maximum; "recommended cert" is the mainstream-agency level operators usually ask for, not a legal rule. Currents and visibility change daily, so treat everything here as planning ranges.
Middle Arch is the mellow sibling of the Knights' famous slots, wide enough to feel like a boulevard and shallow enough for long, gas-friendly dives. Scorpionfish impersonate rocks along the walls, moray eels share crevices with crayfish in a reserve where both grow old, and the kelp fringe swirls with demoiselles and butterfly perch. Nudibranch hunters do some of their best work here, and a small side cave scribbles bonus dark corners onto the map. Guides use it as the all-weather, all-levels anchor of a Knights day, and it never feels like a consolation prize.
The moment you come for: Broad easy archway, crayfish and morays in the cracks, prime nudibranch hunting
Topography: Broad archway with kelp-edged walls, boulder slopes, and sandy patches
Know before you splash
Hazards: Mild surge near the walls in swell; otherwise benign.
Who you'll meet
Nudibranchs
Blue Shark
Bottlenose Dolphin
Orca (Killer Whale)
"Charted here" species were listed by our editors from the sources on this page. Counts are GBIF occurrence records: observations logged within about 5 km of the charted position since 1990, matched only against the species in our catalogue. They show what has been seen there, not a promise of what you will see.
For photographers
Wide angle: ★★★★☆ · Macro: ★★★★☆ (editors' 1–5 rating of what this site gives each style of shooting)