Hallim (Hyeopjae) Caves – Jeju Island – Moseulpo & West Coast Dive Site

12m Max

5-15m Vis

boat

Site Overview

Hallim (Hyeopjae) Caves is one of Jeju Island – Moseulpo & West Coast's most rewarding dive sites, offering eroded lava-tube swim-throughs at 5 to 12 metres with glassfish swarms, lionfish, and octopus in a unique volcanic cave environment. 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 water temperatures ranging from cool winter lows to comfortable summer highs, Hallim (Hyeopjae) Caves 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 reef gardens teeming with juvenile fish to deeper sections where larger species patrol the structure. South Korea's position at the convergence of warm and cold ocean currents ensures rich species diversity with both subtropical and temperate 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. The macro life diversity at Korean dive sites makes them particularly rewarding for underwater photographers and naturalists who appreciate the abundance of unique species. Whether searching for nudibranchs among the volcanic rocks or observing larger pelagic visitors, Hallim (Hyeopjae) Caves delivers memorable underwater experiences throughout the diving season.

Dive Briefing

"Begin the dive at the shallowest point of Hallim (Hyeopjae) Caves and take a moment to orient yourself before descending along the submerged lava tube system. Maintain excellent buoyancy throughout the dive to protect the fragile coral formations and diverse marine life inhabiting the reef structure. Swim along the formation exploring the various depth zones while observing the diverse habitats and marine species that occupy each zone. Check overhangs, ledges, and crevices for resting moray eels, lionfish, and cryptic critters that shelter from the current. Pay special attention to the coral bommies, sandy patches, and rock crevices where smaller species like nudibranchs, seahorses, and frogfish can be found with careful observation. Monitor your depth and remaining NDL carefully throughout the dive and maintain conservative ascent profiles. Keep your dive buddy in visual contact and communicate regularly using standard hand signals. Complete your safety stop at 5 meters deploying your DSMB before surfacing near the boat, watching for boat traffic overhead during your ascent."