Tucked between Halmahera and Bacan Islands in northeastern Indonesia, the Patinti Strait—also known as the Bacan Strait—remains one of Southeast Asia’s best-kept diving secrets.

At its narrowest stretch, a series of small islands interrupt the tidal flow, creating fierce currents that surge through the channel at speeds of up to 2.5 meters per second. These currents act as a lifeline, funneling in nutrient-rich waters that fuel an explosion of marine biodiversity. Visibility regularly exceeds 20 to 30 meters, making it a paradise for underwater photographers and thrill-seekers alike.

Beneath the surface, divers are treated to a high-energy underwater world: adrenaline-pumping drift dives, thriving coral gardens, and bommies swarming with reef fish. Blacktip reef sharks patrol the blue, while macro enthusiasts will find sheltered coves brimming with critters. The reefs here are not just healthy—they’re alive in every sense of the word.

One of the strait’s crown jewels is Kusu Island, a hotspot for spotting the elusive Halmahera Epaulette Shark, a species only formally described in 2013. These nocturnal, walking sharks are rare elsewhere but relatively common here—on one night dive, I counted five within ten minutes. Thanks to experienced local guides, your chances of a sighting are impressively high.

Though the Patinti Strait is far removed from the usual dive circuits, it’s surprisingly accessible, with daily flights from Ternate to Labuha. And the remote location means you’ll often have entire dive sites to yourself.

Some places stay with you long after the tanks are empty. I still dream of early mornings on my bungalow deck, coffee in hand, watching the sun rise as baby blacktip sharks glide through the shallows below—a moment of stillness before another day of world-class diving.