Bubble Cave is one of the smaller novelty features of North Solitary Island's varied reef system, a rock cavity where trapped air forms a pocket that divers can rise into briefly during the dive — a quirk of the island's geology that has made the site a minor local attraction alongside its more conventional reef diving. It sits within the same general area as Anemone Bay and Fish Soup on North Solitary Island, and is generally worked into a broader day of diving around the island rather than targeted as a stand-alone destination. Outside the cave feature itself, the surrounding reef in 6 to 18 m holds a fairly typical selection of Solitary Islands life: schooling bullseyes, resident crayfish, wobbegong sharks and moray eels occupy the ledges and crevices, and the general visibility and water quality matches the rest of North Solitary Island — usually 15 to 25 m and among the best in the marine park given the site's distance from the mainland and any river outflow.

The cave itself needs to be treated with appropriate caution: while the air pocket inside is a novelty, it should never be relied upon as a source of breathable air in an emergency, since its composition and quality are unmonitored and it can trap surge in anything but genuinely calm conditions. Divers should only attempt to enter the air chamber under the guidance of a Wooli Dive Centre divemaster familiar with the site, and should treat the approach as an overhead environment requiring the same caution as any other small cave or swim-through. As with the rest of North Solitary Island, the site requires the full 75-minute boat commitment from Wooli and is genuinely at the mercy of the day's swell and current.

Wooli Dive Centre is the only operator serving this section of coast and departs from the Wooli River wharf in the small village of Wooli, reached via Wooli Way off the Pacific Highway/Grafton-Wooli Road. The river mouth has a shallow, shifting bar that the operator's purpose-built jet-propulsion vessel (able to run in very shallow water) is specifically equipped to cross; private trailer boats should not attempt this bar without strong local knowledge. From the wharf it is roughly 25 minutes to North Solitary Island's southern sites and up to 90 minutes to Pimpernel Rock in the north of the marine park, weather dependent.

Wooli Dive Centre requires a minimum group size (around six divers) to run a charter to the more remote sites.

North Solitary Island and Pimpernel Rock sit fully in the open ocean north of the more sheltered Coffs Harbour grounds, so trips depend on a genuinely settled weather window — under about 1.5 m swell and light-to-moderate winds — and are cancelled more often than the South Solitary Island trips run from Coffs. The Wooli River bar itself is shallow and can be dangerous in a big swell or a strong outgoing tide; the dive centre's shallow-draft, high-powered vessel is built specifically to manage it, but the bar can still close the operation down on a bad day. Visibility offshore is normally excellent, in the order of 15-30 m, but summer brings warmer water (up to 25°C) with more current from the East Australian Current, while winter is cooler (down to about 18-19°C) but often calmer.

Cyclone-influenced swells from the Coral Sea can affect this coast in late summer/early autumn even without a direct cyclone hit.

Approach the cave entrance cautiously in calm conditions, enter to find the internal air pocket if briefed to do so, then continue around the surrounding reef at 12-18 m for bullseyes and crayfish before returning to the boat.

Included on Wooli Dive Centre's North Solitary Island itinerary when sea conditions are calm enough for the cave to be entered safely.