Shenzhen He or Sham Chun River is a river in southern Guangdong. Together with Shaotoujiao He / Sha Tau Kok River, it is the natural boundary between Shenzhen City and the Hong Kong Special Administrative Region. This makes it a border between the mainland and Hong Kong.
The river is located between North Hong Kong and South Shenzhen. The source of the river is the Wutong Shan mountain. The river flows into the bay of Hau Hoi Wan. Along the river side of Hong Kong and the mainland, fences have been placed with barbed wire since 1949. The border has been strictly monitored by both sides since the 1960s and walls were built. During the Cold War there were many surveillance towers. The communists were afraid of great emigration from the Shenzhene people to Hong Kong and the British were afraid of the huge influx of refugees from the mainland China. The wall looked like a milder version of the iron curtain.
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