Guishan Island / Turtle Island – Yilan Dive Site

Site Overview

Guishan Island / Turtle Island is one of Yilan's most rewarding dive sites, offering famous for its Milk Sea hydrothermal vents where divers experience underwater volcanic sulfur plumes and encounter the unique endemic Xenograpsus testudinatus crabs that live nowhere else on Earth in one of the world's most extraordinary volcanic diving environments. The site's healthy marine ecosystem supports diverse fish populations and vibrant coral formations throughout the diving season, creating an underwater landscape that rewards repeated exploration. With warm water temperatures and exceptional visibility depending on conditions and season, Guishan Island / Turtle Island provides excellent conditions for underwater exploration across all certification levels. The site's diverse topography creates multiple habitat zones supporting different species at various depths, from shallow coral gardens teeming with juvenile fish to deeper sections where larger species patrol the structure. Taiwan's position in the path of the Kuroshio Current ensures rich species diversity with both tropical reef and pelagic influences contributing to the marine communities. Nutrient-rich waters sustain abundant filter-feeding invertebrates including gorgonian sea fans, sponges, and soft corals that add color to the underwater scenery. Whether searching for macro critters among the reef bommies or observing larger pelagic visitors, Guishan Island / Turtle Island delivers memorable underwater experiences.