TAIPEI (Taiwan News) — China is building out its coastal military infrastructure to expand its list of staging grounds for a potential invasion of Taiwan, with new facilities popping up along a broad swath of coastline.

A report by the Wall Street Journal based on satellite data and other open-source information indicates China has been hard at work building airfields, naval facilities, and hardening infrastructure to prepare for a war it may one day decide to start.

Near Shanghai’s Pudong Airport, the main international gateway to the city, China has constructed a large naval base. In May it was photographed hosting a dozen amphibious transport ships, including ones that can carry tanks, helicopters, and between them about 5,000 soldiers.

The same base featured hardened fuel tanks, which the WSJ quotes a US defense expert as saying could withstand cruise missile attacks — though not penetrating warheads. According to the expert, the hardening of the fuel tanks suggests China anticipates the base would come under fire in a conflict.

The Pudong base is also being integrated into China’s high-speed rail network, presumably to aid in faster troop deployment.

Another naval base in Yueqing Bay in southeastern Zhejiang Province — closer to Taiwan — boasts a new mile-long pier where about 20 ships that could be used in an invasion were recently photographed. These included tank transports, landing craft, coast guard vessels, and tankers.

Fujian Province is home to a new helicopter base that would be able to fly sorties within range of Taiwan and that in particular could prove crucial in an invasion of Taiwan’s Penghu archipelago. The helicopter base, which satellite photos of recently cleared land indicate is still expanding, has also reportedly been in use as a drone facility.

Meanwhile, two new civilian airport projects in Fujian appear aimed at boosting China’s ability to wage war. The first, the Xiamen Xiangan International Airport, is being constructed on Dadeng Island in the Taiwan Strait, near Taiwan’s Kinmen. The airport’s size and logistics capacity would make it a prime staging ground for invading forces.

The report notes a second strategic airport expansion further north near Fuzhou, with additional runway construction.