High Island sits within the Sai Kung area and is part of the UNESCO Global Geopark. The three sites cover a range of underwater terrain: the artificial reef structure at East Dam, a wreck at Yin Tsz Ngam, and a shallow shore-entry reef at Tan Ka Wan. Depths stay within twelve metres across all sites, and conditions are generally mild, making the area suitable for beginners. Nudibranchs, wrasses, boxfish, and snappers are among the species regularly encountered. Access is by boat or shore depending on the site, with operators based in Sai Kung.
Monthly water temperature across High Island's sites, from satellite sea-surface data corrected for depth. The band shows the site-to-site spread.
Water temperature follows a marked seasonal swing, sitting around nineteen degrees in mid-winter and reaching twenty-nine degrees from late summer into early autumn. The warmest months offer the most comfortable diving with minimal exposure protection needed, while a five-millimetre wetsuit suits the cooler winter period. Conditions at all three sites are generally mild, though boat traffic is a hazard to monitor on weekends.
Water temperature around High Island ranges from about 19°C in January to 29°C in September, based on satellite sea-temperature data for its dive sites.
In the warm season (about 29°C) a rash guard or 3mm shorty is comfortable in High Island; in the coldest months (about 19°C) step up to a 5mm suit.
Fin maps 3 sites in High Island (3 scuba diving sites).
1 more site to explore
