How China transformed submerged reefs into a chain of militarized artificial islands

Countries & Cities · Published 30 September 2026 Swipe more like this →

In short: Between 2013 and 2016, China executed a massive land reclamation project in the South China Sea, dredging millions of cubic meters of sand to build artificial islands atop submerged reefs. This controversial strategy, dubbed the Great Wall of Sand, has sparked intense geopolitical friction and severe, long-term environmental degradation.

The project involved seven specific locations in the Spratly Islands, where China utilized massive, specialized dredgers to pile sand and concrete onto reefs that previously sat about one meter below the water's surface. By late 2016, these efforts had created roughly 1,300 hectares of new land. Analysts describe the result as a methodical network of air and sea-capable fortresses, complete with deep-water ports, barracks, and runways on sites like Fiery Cross, Mischief, and Subi Reefs. While China maintains these facilities are intended to improve living conditions and provide navigational aid, they have also installed significant weaponry, including anti-aircraft systems.

The legal status of these structures remains a flashpoint. In 2016, the Permanent Court of Arbitration ruled that China’s maritime claims in the region lacked historical basis and that the artificial islands were constructed within the Philippines' exclusive economic zone. Under international maritime law, features built on the seabed do not generate territorial waters, and the court concluded that China lacked the authority to build them. China rejected this ruling as null and void, asserting its right to protect its sovereignty and monitor the surrounding airspace.

Beyond the geopolitical tension, the environmental toll is profound. The dredging process destroyed vital reef ecosystems, and the resulting sediment plumes have smothered marine life, blocking sunlight essential for coral survival. Experts estimate that these damaged reefs may require 10 to 15 years to recover, if they recover at all. Furthermore, the destruction of these habitats disrupts migration routes and depletes fish stocks, violating international environmental obligations that mandate the protection of fragile marine ecosystems. The project has drawn strong opposition from the G7 and the United States, which continues to conduct freedom of navigation operations near the sites.

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