Big Drop-Off (Koh Tang) – Koh Tang & Outer Islands Dive Site

40m Max

10-30m Vis

boat

Site Overview

Big Drop-Off (Koh Tang) is a sheer wall from 15 to 40 metres with grey reef sharks, tuna, occasional whale shark, and dramatic vertical reef structure on Koh Tang's exposed western face dive site in the Koh Tang & Outer Islands region of Cambodia, situated among the diverse reef systems and island formations that make this Southeast Asian nation one of the Gulf of Thailand's most emerging diving destinations. The site features depths from 15 to 40 meters with an average depth of 28 meters, offering an extraordinary underwater experience showcasing the remarkable combination of fringing reefs, offshore islands, and historical wrecks that Cambodia's waters are celebrated for among adventurous divers seeking less-crowded tropical diving. Renowned for its encounters with Grey Reef Shark, Tuna, Whale Shark and other remarkable marine species, Big Drop-Off (Koh Tang) attracts divers seeking thrilling underwater adventures in one of Southeast Asia's most distinctive and developing diving destinations. The Cambodian coast creates a fascinating underwater landscape of fringing reefs, rocky islands, artificial reef structures, and natural coral communities that provide habitat for diverse marine life in the warm waters of the Gulf of Thailand. The unique geography of Cambodia's coastline with its chain of offshore islands creates varied habitats supporting abundant marine life including tropical reef fish, sharks, rays, and pelagic visitors found in few other destinations. Visibility typically ranges between 5 and 30 metres depending on site location and season with the outer island sites offering the clearest water. Water temperatures range from 26 to 31 degrees Celsius year-round making a 3mm shorty standard equipment. Big Drop-Off (Koh Tang) consistently ranks among the top dive sites in the Koh Tang & Outer Islands region, drawing dedicated divers who seek exceptional reef diving experiences combining rich marine biodiversity with the excitement of exploring Cambodia's developing underwater frontier.

Dive Briefing

"A typical dive at Big Drop-Off (Koh Tang) begins with entry from the dive boat, descending to the main formation at approximately 28 meters while orienting yourself and equalizing before exploring the remarkable Cambodian underwater landscape. Once established on the main formation, divers should swim along the reef structure or wreck exploring diverse habitats, moving between coral encrustations, swim-through sections, and sandy areas while maintaining excellent buoyancy control to protect the marine life colonising the structure below. The most productive depth zone is between 18 and 35 meters where the highest concentration of reef fish species and photographic opportunities are abundant. Navigate along the reef or wreck edge watching for pelagic species in the surrounding water, and check the overhangs, crevices, and ledges where moray eels, groupers, and larger reef fish shelter from the current. Cambodia's reef and wreck environments require careful awareness of marine life hazards and potential entanglement when exploring interior sections. Monitor depth and NDL particularly near 40 meters on the deeper sites, and always maintain a conservative approach to dive planning given the distance to the nearest hyperbaric facilities. Scan the surrounding water for approaching pelagic species including eagle rays and barracuda that patrol the reef edges. Conclude the dive with a slow ascent and a generous safety stop at 5 meters, deploying your DSMB before surfacing and signaling the dive boat for pickup."