Beigan North Sea Tunnel Introduction
The artificially excavated Northern Sea Tunnel is a masterpiece of engineering. In 1968, the "Northern Sea Project" commenced in the Matsu area for strategic purposes, resulting in the creation of several "underground docks" specifically for the parking of guerrilla war vessels. Nowadays, after the military's release, it has become a unique "battlefield landscape" in Matsu, and if one has not visited the Northern Sea Tunnel, it is as if one has not truly experienced Matsu. The Northern Sea Tunnel is located along the Tieban coastline, featuring a waterway that delves deep into the mountain and traverses through rock walls in a "井" (well) shaped pattern. The waterway is 18 meters high, 10 meters wide, and 640 meters long. The water level can reach up to 8 meters at high tide and drop to 4 meters at low tide. The entire walking trail extends 700 meters and takes about 30 minutes to complete, but visitors must align their visit with the tidal movements, as entry is only allowed during low tide. This underground tunnel can accommodate over a hundred landing craft and was considered a highly challenging engineering project at the time. It involved the mobilization of two divisions, three infantry battalions, one engineering battalion, and a mixed group of three teams comprised of dump truck units, all working around the clock to complete the construction over 820 working days. Due to the rudimentary construction equipment, the project relied heavily on manual labor; explosives were used for blasting, and workers used chisels to excavate the granite walls. Many servicemen lost their lives in the process, demonstrating the project's immense difficulty and grandeur, rightly deemed a work of extraordinary craftsmanship. In the past, during times of military tension, the Northern Sea Tunnel attempted to serve as an underground dock for supply purposes. Today, as people enter the deep tunnel, the majestic rock walls and the dim floating reflections inspire awe among visitors. Note: The tunnel is open for public visits, but entry during the day must align with the tidal changes. Visitors are advised to pay attention to the tidal difference! Nighttime Boat Ride: A Great Place to See Blue Tears In recent years, due to the discovery of "blue tears," and considering that the tunnel entrance has minimal light pollution, the Northern Sea Tunnel has become one of the hot spots for observing blue tears in Nangan. Riding a boat slowly into the tunnel to seek the faintly glowing halo is an experience worth exploring. Note: The phenomenon of blue tears is natural and its conditions cannot be predicted. Please refrain from using flash photography. For safety reasons, standing up or changing seats is prohibited while the boat is in motion.
