1. The road gradually widened until we found ourselves in a large valley.
    路渐渐宽了起来，最后我们走进了一个大的山谷。

1. 峡谷：你可以用三种不同的方式来浏览这个红色星球:1)火星的高低立视图(elevation map),我们用不同颜色标注了上面的山峰 (peak) 和峡谷 (valley祝你的火星之旅开心!

1. 山谷;（尤指）溪谷
    A valley is a low stretch of land between hills, especially one that has a river flowing through it.

    e.g. ...a wooded valley set against the backdrop of Monte Rosa.
           罗莎峰背后树木繁茂的山谷
    e.g. ...the Loire valley.
           卢瓦尔山谷

1. a long depression in the surface of the land that usually contains a river

    Synonym: vale