Satellite Images Show China's Expanded Naval Base in the South China Sea

Yulin Naval Base, a home port for China's submarine fleet in the South China Sea, has undergone a significant expansion in a sign of continued investment in the country's naval capabilities, according to a new report.

Satellite imagery analyzed by maritime security researcher H.I. Sutton revealed that the facilities nearest to Sanya, a resort town on the island province of Hainan in southern China, would be doubled in size, with additional quays and infrastructure being added.

Amid persistent geopolitical tensions in the South China Sea between Beijing and other claimant states, Yulin Naval Base's larger footprint has become a focal point for observers like Sutton, who track the evolving power dynamics in the region.

China's military expansion under President Xi Jinping appears to be following a clear and methodical approach, even as its true nature remains difficult to determine. The growth at the Yulin base also underscores the unmissable naval component of Xi's desire to modernize the Chinese armed forces into a formidable fighting force.

The construction of two new piers at Yulin, which began last year, has progressed swiftly, with the first phase already largely complete, according to Sutton's analysis published on Sunday.

Among the major projects is a new quay on the western shore of Yulin Harbor, which extends beyond the historical inner harbor. This development has prompted speculation regarding the evolving role of the base, particularly in accommodating unmanned platforms, the report said.

According to Sutton's findings, the growth of China's primary naval base in the South China Sea aligns with the nation's broader strategy of developing unscrewed underwater vehicles (UUV).

The new quay, which will measure over 1,500 feet when completed, may be designed to house extra-large underwater drones, Sutton said. As China advances multiple projects of the nature, the need for suitable berthing facilities may have necessitated the ongoing construction at Yulin.

"China also has multiple uncrewed surface vessel (USV) projects, including large ones which will need berthing like ordinary ships," he wrote. "As these uncrewed platforms approach operational status, they will need base facilities, so some construction was expected."

In recent years, air, sea and underwater drones have seen use in the Black Sea in the fighting between Ukraine and Russia. Asian military powers including China, South Korea and Taiwan all have been developing their own variants, although each of their potentially unique technological applications remained unclear.

In a parallel development, a Defense News report in 2022 said two new piers were also under construction at Yulin Naval Base. They were positioned to the north and south of existing structures and linked to newly reclaimed land, it said.

Analysis of satellite imagery at the time showed the presence of a dredger near the base's northern pier in what appeared to be complex expansion work.