Dive sites in Taiwan

Longdong is located within the Northeast Coast National Scenic Area, approximately one hour from central Taipei by car. Public transport options include taking the Taiwan Railways Administration train to Ruifang station, then transferring to a local bus along the coastal road. Several Taipei-based dive shops run regular day trips to Longdong with transportation included, departing early morning and returning by evening. The site has parking areas, changing facilities, and the Longdong Bay Ocean Park provides additional infrastructure including rinse stations and equipment storage.

While diving at Longdong is possible year-round, winter conditions from November through March are challenging. Water temperatures drop to 18 degrees Celsius or lower, the northeast monsoon brings significant wave action and reduced visibility, and marine life activity decreases. The prime season runs from May through October, with July to September offering the warmest water and best visibility. During summer, tropical fish species carried north by the Kuroshio Current make temporary appearances, adding unexpected colour to the temperate reef community.

Longdong is widely used as a training site for Open Water certification courses, making it suitable for complete beginners under instructor supervision. The sheltered bay areas offer shallow, calm conditions ideal for skill practice, while the outer reef edges provide more interesting terrain for certified divers. Many of Taiwan's PADI and SSI instructors conduct their open water training dives at Longdong due to the combination of easy shore access, gradual depth progression, and sufficient marine life to keep students engaged. Certified divers will find the outer walls and boulder fields more rewarding.

The Blue Cave itself on Xiji Islet is primarily viewed from boats, as there are currently no wharf facilities to land on the islet. However, snorkelling and diving in the surrounding waters of the South Penghu Marine National Park is permitted and popular. The cave is best experienced by boat tour, where you can see the stunning blue light effect created by sunlight refracting through the sea cave entrance. Nearby dive sites offer excellent underwater exploration among the basalt formations.

The South Penghu Marine National Park protects vast fields of purple staghorn coral that are rare elsewhere in Taiwan and the broader region. These corals create a striking lavender-coloured underwater landscape that is particularly photogenic. The protected status of the marine park has allowed these coral formations to flourish in shallow, well-lit water. Snorkelling above the purple coral fields is one of the most popular activities in the Penghu Islands.