North Korea has recently unveiled its first nuclear-powered strategic missile submarine, constructed at a major port and naval base in Sinpo City on the East Sea. This revelation, confirmed on Wednesday, suggests that Pyongyang intends to use this location as a launchpad for its nuclear submarine fleet to project power into the Pacific.
Intelligence gathered by News1 indicates that the 8,700-ton nuclear submarine, showcased by North Korea on December 25, was built over several years at a specialized facility in Sinpo.
This is the same site where North Korea claims to have built the Hero Kim Gun-ok submarine in 2023, which it touted as its first tactical nuclear attack submarine. U.S. and South Korean intelligence classify the Kim Gun-ok as a Sinpo-C class ballistic missile submarine (SSB), a conventionally-powered vessel capable of launching nuclear-tipped ballistic missiles.
Following its launch on September 6, 2023, the Kim Gun-ok submarine underwent approximately a year of outfitting in the Sinpo shipyard’s dry dock before reportedly relocating to a secure anchorage in Sinpo in December 2024.
North Korea’s decision to construct its inaugural nuclear submarine base in Sinpo underscores the strategic importance of this location for its underwater warfare capabilities.
Sinpo’s geography is particularly advantageous, facing Mayangdo Island, North Korea’s largest East Sea island and home to its 4th Fleet. The proximity of Mayangdo naval base, a mere 2.5 miles (approximately 4 km) from Sinpo’s coastline, provides a natural shield for submarine operations.
By concentrating its nuclear and tactical attack submarines in Sinpo, North Korea aims to protect these assets from potential enemy strikes while establishing a forward operating base for Pacific operations.
Furthermore, Sinpo is poised to become a cornerstone of Kim Jong Un’s ambitious blue-water navy initiative, alongside Chongjin. Earlier this year, North Korea launched the Kang Gun-ho, the second of its new class of 5,000-ton destroyers, from the Chongjin Shipyard, located about 143 miles (approximately 230 km) northeast of Sinpo.
The strategic location of Chongjin Shipyard, in close proximity to Russia’s Pacific Fleet headquarters in Vladivostok, has fueled speculation about potential naval cooperation between Pyongyang and Moscow. This alignment could be part of a broader strategy to challenge U.S. and Japanese maritime dominance in the region.
North Korea has also announced plans to transfer the Choe Hyon-ho, another 5,000-ton destroyer built in Nampo on the West Sea, to its East Sea Fleet early next year. These developments signal North Korea’s intent to establish a formidable naval presence in the East Sea, centered around its new destroyers, nuclear submarines, and tactical submarines.
