The reef in front of the Marmion Angling and Aquatic Club has long been a popular Perth shore dive, and in 2022 DBCA and partners opened the MAAC Dive and Snorkel Trail here: a 400 m route marked by about 20 underwater plinths with interpretive information and artwork, in 2–6 m. The trail sits within Marmion Marine Park and is designed for all levels.

The reef is limestone with nooks, crannies, small inlets and ledges, some nearly drying at low water. Marine life hides in every gap. Weedy seadragons are the best-known residents, and divers also see bream, red-lipped morwong, trevally, scalyfin, banded sweep, stripeys, tarwhine, goatfish, western blue devils, zebrafish and schools of pomfret, with Port Jackson sharks, eagle rays and stingrays on the sand and octopus in the crevices. Staircase sponges and other sponges grow on the reef.

The wheelchair-accessible ramp makes this one of the most accessible reef dives in Perth. The main issue is surge: the reef lies close to the surface, and waves breaking on it can push divers around even on calm days. It needs low swell and light easterly winds, and summer afternoons are best avoided.

The trail suits families, snorkellers, beginner divers and photographers. With a second, deeper reef 80 m south, experienced divers can extend the dive. Boats and kayaks use the club ramp, so tow a flag.

Water temperatures on this coast range from about 17 °C in late winter to 22–23 °C in late summer, when the warm Leeuwin Current is strongest, so a 5 mm wetsuit suits summer and a 7 mm suit with a hood is more comfortable from June to October.

Drive north on West Coast Drive to the Marmion Angling and Aquatic Club, about 15 minutes north of the city and 10 minutes south of Hillarys Boat Harbour. Park in the club car park or on the road, kit up (keep valuables out of sight) and walk down either side of the club to the boat ramp. Enter from the ramp; the reef lies to the left (south).

A second, deeper reef lies about 80 m south.

Perth's northern coast is far more exposed to ocean swell than the Cockburn Sound sites. The site is considerably affected by swell over 1 m, and it needs low swell (about 1 m or less) and preferably a light easterly. Waves breaking over the reef have force even on calm days, and surge can push divers onto reef only 0.5 m below the surface.

Avoid the afternoon Fremantle Doctor in summer; it becomes surgy and dangerous in lumpy weather.

Enter from the boat ramp, turn south and follow the plinths along the reef in 2–6 m. Continue to the deeper second reef about 80 m south if conditions allow, then return along the trail to the ramp, timing the exit between waves.

Mostly independent divers and snorkellers; Perth dive shops run occasional guided snorkels and training dives on the trail.