The Glenelg Jetty is Adelaide's best-known jetty, but as a dive site it is modest: a shallow dive of 2-4 m among the piles and the bottom debris that has accumulated beneath them over the years. The Marine Life Network lists it as a good day dive and an excellent night dive, and records shells, nudibranchs, cuttlefish, octopus, blennies, cowfish, leatherjackets, wrasse and several species of sea star. The current jetty is a replacement for Glenelg's original, much longer jetty of the 1850s, which was destroyed by storm in 1948; the Glenelg Blocks offshore are remnants of the mooring system from that earlier shipping era.

The piles today carry algae, sponges and small invertebrates, and the scattered debris on the sand provides hiding places for octopus and small fish. At night the site comes alive, with cuttlefish hunting and invertebrates emerging, which is why local divers value it as a convenient night dive right in the city. The drawbacks are shallow depth, variable visibility and crowds.

Heavy seas stir up the sand and create strong surge, and in summer the beach and jetty are packed with swimmers and anglers. The best time to dive is on a calm night or early morning after offshore winds. Glenelg Jetty suits new divers practising skills, macro photographers and anyone wanting a quick night dive near the Glenelg dive shops.

It pairs well with a boat trip to the Dredge in the morning. Keep clear of fishing lines and be highly visible: carry a torch and surface marker so jet skis and boats near Holdfast Shores can see you.

Take the tram from the CBD to Moseley Square or drive via Anzac Highway (20 minutes). Paid parking is available around Moseley Square, Holdfast Shores and side streets. Gear up on the foreshore and enter from the beach beside the jetty, swimming out along the piles.

There is no diver staircase, so exits are via the beach. The site is very busy with swimmers in summer.

Very shallow and west-facing: heavy seas stir the area and create strong surge, according to the Marine Life Network. Dive only in flat conditions after easterly (offshore) winds, preferably at night or early morning. Visibility is poor after westerlies and after rain, when the Patawalonga and stormwater outflow affect the bay.

Tidal range is small but low tide leaves very little water.

Enter beside the jetty, swim out to the deeper half, then weave slowly between piles at 2-4 m, searching the bottom debris with a torch. Return along the opposite side.

No regular operator; Adelaide Scuba (Glenelg North) and The Dive Shack are within walking/driving distance for fills and local advice.