Puzhuangsuo Castle, National heritage castle in Cangnan County, China

Puzhuangsuo Castle is a stone fortress in Cangnan County with defensive walls and architectural features from the Ming Dynasty period. The structure demonstrates the military design typical of that era, built to protect and control the surrounding coastal region.

The fortress was built over 630 years ago during the Ming Dynasty and represents military architecture of that period. It gained national protection status in 1996, securing its place among China's most important cultural heritage sites.

The name changed over time: it was first called Puzhou Suo, then merged with the Zhuangshi Suo garrison and became Puzhuang Suo, now shortened to Pucheng. Inside the walls stand a City God temple (Chenghuangmiao) and a Mazu temple, both still part of village life in Pucheng.

The castle stands at the foot of hills near the Zhejiang–Fujian border in Pucheng township, Cangnan County. Its walls form a round north side against the mountain and a square south side facing the sea, with three square barbicans on the east, south and west. A moat fed by the Pu River rings the walls, so walk the circuit to grasp the layout.

The walls form a "round heaven, square earth" plan: the northern rampart curves in an arc against the hillside, while the three barbicans on the east, south and west sides are square. The perimeter measures about 2,550 m, roughly five li and thirty paces, and a moat fed by the Pu River rings the outside.