Battle of the Barrier
1840 CE.
Shown on the map at 22.215°, 113.549°.
The Battle of the Barrier (Chinese: 澳門之戰) was fought between British and Chinese forces at the boundary separating Macao from mainland China on 19 August 1840 during the First Opium War. Located in modern-day Portas do Cerco, the Macao Peninsula was connected to Xiangshan Island by a narrow isthmus about 100 m (330 ft) wide and 1.2 km (0.75 mi) long. A wall called the Barrier was built across the isthmus in 1573, and it served as Macao's border.
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