The North Wall is the Seaway's less-visited side: the breakwater on the South Stradbroke Island shore, reached only by boat. UniDive and Gold Coast Dive Adventures list it as one of the four main Seaway dive areas alongside the South Wall and its pipes, the South-West Wall beach and Wave Break Island. Depths are similar to the south side, from about 5 m near the top of the rocks to 20 m at the base.

Because it is harder to get to, it sees far fewer divers than the South Wall, and the fish life reflects the extra exposure to the ocean. Experience Gold Coast singles out pelagic activity here, including barracuda, mangrove jack and mulloway, and the same giant groupers, rays and wobbegongs found on the south side patrol the rocks. The boulders harbour moray eels, lionfish, scorpionfish and stonefish, and the crevices are good for crayfish and nudibranchs.

Eagle rays, cownose rays and shovelnose rays pass over the sand at the base. Bigeye trevally often school in the channel. As with the rest of the Seaway, the tide rules.

Dives are timed for the end of the flood and the high-tide slack, when clean ocean water fills the entrance and the current eases; on the ebb, the channel runs hard and the water is murky. The North Wall also faces more of the easterly swell that wraps into the entrance, so it may be rougher than the south side on the same day. For divers who know the South Wall well, it offers the same Seaway experience with fewer people and a better chance of pelagics.

Boat access only – the North Wall is on South Stradbroke Island and has no road access. Gold Coast Dive Adventures runs boat dives from Runaway Bay Marina (about 10-15 minutes down the Broadwater); private boats launch at the Seaway/Broadwater ramps. Boats drop divers beside the wall and follow them; do not anchor in the navigation channel.

Stay close to the rocks and away from the channel centre.

Tidal site – dive only towards the end of the incoming tide and the high-tide slack (enter roughly 30-60 minutes before high tide; be out within about an hour of the turn). The ebb runs very hard and brings turbid Broadwater water; treated sewage is vented from the short pipe after high tide. Large easterly swells push surge into the entrance.

Visibility 3-15 m, best on big high tides in dry weather. The North Wall is more exposed to easterly swell wrapping into the entrance than the South Wall.

Drop in near the wall 30-60 minutes before high tide, descend to the base of the rocks and swim along the wall, watching the channel side for pelagics. Ascend beside the rocks with a DSMB so the boat can pick you up clear of channel traffic.

Gold Coast Dive Adventures (Runaway Bay) – boat dives at high tide; UniDive and other clubs occasionally.