Shanhaiguan-Where the Great Wall reaches the sea

• 作者: BRUCE CONNOLLY
• 来源期刊: 中国周刊
• 学科: 地球科学
• 关键词: VALLEY forts TODAY potentially protected reaches TOWER STRENGTHENED LADDER FILLED
• 年，卷（期）: zgzk_2003,（9）
• 页码范围: 12-15
• 页数: 4页
• 分类号: K928

摘要

【正】 The Great Wall was constructed, modified and strengthened over a long period of time to protect Ancient China from northerly invasions. In places such as valley bottoms there were potentially weak points where passes or gaps existed through the wall for trade routes. These points had to be particularly well protected. Some of the great forts still existing today were built for that purpose. Two of the most famous passes are Jiayuguan Fort in