Diving & Travel Guide to Sumbawa & Saleh Bay

Sumbawa Island and its vast Saleh Bay represent one of Indonesia's most underrated and least-visited diving destinations, offering a remarkable combination of pristine reefs, whale shark encounters, and volcanic island exploration far from the tourist crowds of neighboring Bali and Lombok. The northern coast of Sumbawa faces the Java Sea and benefits from nutrient-rich waters that support healthy coral systems and diverse marine ecosystems. Moyo Island, a private island nature reserve in Saleh Bay, provides world-class diving on its fringing reefs with abundant reef fish, turtles, and occasional reef shark sightings in crystal-clear waters. The real draw of Saleh Bay, however, is the seasonal aggregation of whale sharks that gather to feed on the plankton-rich waters, particularly around the traditional fishing platforms (bagans) that dot the bay. Satonda Island, a small volcanic island north of Sumbawa, offers the unique experience of diving on reefs surrounding an active volcanic crater, with the added topside attraction of a crater lake accessible by a short hike. The southern coast of Sumbawa features dramatic limestone cliffs and exposed Indian Ocean reefs that attract experienced divers seeking powerful currents and pelagic encounters. With very limited tourism infrastructure and almost no international dive operators, Sumbawa delivers a genuine frontier diving experience for those willing to venture off the beaten path. Geologically, the region is dominated by the massive Mount Tambora, whose cataclysmic eruption in 1815 reshaped the island's topography and created the unique volcanic features found underwater today. This volcanic legacy provides a nutrient-dense environment where coral colonies can thrive, creating a resilient marine ecosystem that is a testament to the regenerative power of nature.