The terrain is mostly mountainous, with fast flowing rivers and few forests.

地形上几乎大部分是山地，河流湍急，植被稀少。

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Major rivers flowing through Beijing include Yongcing river, Chaobai river, north Canal and Juma river that mostly originated in the northeastern mountainous areas of Beijing.

穿过城市的主要河流包括永定河，潮白河，北运河和拒马河。它们大多源于北京东北部的山脉地区。

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After surviving my late day mostly lost in the mountainous misty tea plantations, i tried to plan a more gentle day, but still with mountains.

在几乎整整一天迷失在满布茶园的山林后，我决定给自己安排比较温和的行程，不过当然还是以爬山为主。

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The tremors struck mostly mountainous areas, causing landslides that blocked some roads.

BBC: China earthquake death toll rises in Yunnan and Guizhou

U.S. officials estimate that there are only 100 or so al Qaeda militants in Afghanistan, mostly in the mountainous northeastern provinces.

WSJ: Operation Is Blow to al Qaeda, Taliban