The Sandbar Barge is a small landing-type barge that rests upright on the bottom on the western side of the sandbar outside Cullen Bay, with its bow door down. Its origin and the circumstances of its sinking are not recorded in the sources consulted. Shifting sand has covered one side of the barge, which is why it is difficult to find with a depth sounder and why DSAC recommends an accurate mark.

Despite its size, DSAC rates it an excellent dive because of the fish it holds: golden snapper, black jewfish and cod crowd around the exposed structure, and the lowered door creates a sheltered pocket on one side. The barge is small enough that only a few divers can work it at once without silting the site, so it is best done as a small-group club dive. At 24-26 m, bottom time is limited and the site sits close to the Cullen Bay entrance channel, so a good boat cover is important. It suits Advanced divers who want a quick, fishy wreck close to the marina, and it works well on a morning when a longer run across the harbour is not practical. The sandbar itself is a landmark for Darwin boaters, which makes the approach straightforward in daylight. Because so little is documented, divers who visit are encouraged to record the barge's condition and share it with the club. Treat it as an exploratory dive and note the depth, orientation, condition and fish life you find, since the published record for this barge is thin.

Boat only; a short run of a few minutes from Cullen Bay Marina or the Cullen Bay public ramp out to the sandbar west of the marina entrance. The barge is partly covered by sand and hard to pick up on a depth sounder, so an accurate GPS mark from local divers is essential. Time the dive for neap high-water slack and keep the group small.

Tide is everything in Darwin Harbour: the spring range is 7-8 m and tidal streams run hard through the harbour, so diving is generally only possible on neap tides (range under about 3-4 m), timed to the slack at high water when clearer ocean water sits over the site. Spring tides bring strong currents and silt-laden water with near-zero visibility. The dry season (May-October) gives the most consistent conditions; the south-east trade winds can chop up exposed water in the afternoon, so mornings are best.

In the wet season (November-April) run-off from the rivers and creeks drops visibility, afternoon storms build quickly, and the harbour is in cyclone season; box jellyfish are present October-May.

Small groups only. Descend the shot to the upright barge at about 24-26 m, circle the exposed side and the lowered door, check under the edges for cod and jewfish, and return to the line within a short no-deco time.

No regular operator; dived by Darwin Sub Aqua Club in small groups on neap days.