Longdong (Dragon Cave) Northeast Coast

Keelung · New Taipei City · Taiwan

Longdong occupies a dramatic stretch of Taiwan's northeast coast where volcanic sandstone cliffs drop into the Pacific, creating sheltered coves and rocky reefs roughly one hour from Taipei. For generations of Taiwanese divers, Longdong is where diving begins. It is the island's most popular training site, the place where most certifications are earned, and for many, the first glimpse of the underwater world. The geology creates a natural amphitheatre. Towering sedimentary rock walls curve around a bay protected from the northeast monsoon. Within the bay, coves provide progressively deeper water over rocky substrate, ideal for structured dive training. The main entry is a concrete ramp at the Longdong Bay Ocean Park, with changing facilities and equipment rental. Beneath the surface, the rocky reef supports a temperate marine community richer than first impressions suggest. Boulder fields create overhangs, crevices, and swim-throughs sheltering impressive invertebrate populations. Octopuses are common, and nudibranchs are abundant and diverse across the site's microhabitats. The real magic happens during summer when the Kuroshio Current pushes subtropical water close to shore. Tropical visitors appear: butterflyfish, angelfish, and occasional moorish idols add unexpected colour to the temperate reef. Cuttlefish hover in the water column, scorpionfish sit motionless, and patient divers find seahorses clinging to soft corals on the outer wall sections. Longdong's proximity to Taipei gives it significance beyond its marine merits. It is the gateway through which Taiwan's growing diving community passes, and weekend mornings during summer see dozens of groups entering the water, creating a communal atmosphere that is part of Longdong's character. For visiting divers, it may not rank among the world's great sites, but as an introduction to Taiwan's marine environment and diving culture, it is indispensable.