The Bida´s

The Bidas are a pair of dramatic limestone islands at the southern tip of the Phi Phi archipelago in the Andaman Sea that together create one of Thailand's most spectacular advanced diving areas. Comprising Koh Bida Nai and Koh Bida Nok, these sheer-walled pinnacles rise from deep water to offer wall diving, shark encounters, and marine biodiversity that place them among the finest dive sites in the entire Andaman Sea. The two islands present different diving characters. Bida Nok, the outer island, features dramatic wall diving where the limestone plunges vertically into deep blue water, with overhangs, caverns, and crevices decorated in luxuriant marine growth. Bida Nai, the inner island, offers a more varied reef with gentle slopes, coral gardens, and the sandy flats where leopard sharks are most commonly encountered. Together they provide a comprehensive dive experience spanning wall, reef, and sandy habitats. The advanced rating reflects the depth accessible along the walls, the current that can develop between and around the islands, and the open-water location that demands solid diving skills. When the current runs, the diving becomes dynamic and exciting, with fish activity intensifying as predators work the reef edges and plankton concentrations build around the islands. Shark encounters define the Bida experience. Leopard sharks rest on the sandy areas between the islands with remarkable reliability, and blacktip reef sharks patrol the reef edges. The combination of multiple shark species with such consistent sighting rates makes the Bidas one of the most dependable shark diving locations in Thailand. Beyond the sharks, the reef supports extraordinary biodiversity including schools of barracuda, trevally, and the full spectrum of tropical reef species. The soft coral and sponge growth on the walls is exceptional, with vivid colors that make every dive a visual feast. Sea fans of impressive size extend from the limestone, and the shaded overhangs host communities of organisms that create some of the most photogenic scenes in Thai diving. The macro life is equally impressive, with ghost pipefish, nudibranchs, and seahorses found by dedicated searchers. The Bidas represent Phi Phi diving at its absolute best. The combination of dramatic topography, reliable shark encounters, exceptional marine diversity, and the stunning Andaman Sea setting creates a world-class diving experience that fully justifies the Phi Phi Islands' international reputation.