万水千山的英文：
[Literal Meaning]
ten thousand/river/thousand/mountains
ten thousand crags and torrents

[解释]
万道河，千重山。形容路途艰难、遥远。

[Explanation]
a long and arduous journey

[例子]
探险队经过了万水千山，最后终于抵达了目的地——西藏。

[Example]
The expedition crossed a long and arduous journey and eventually arrived at the destination - Tibet.

[英文等价词]
the trails and tribulations of a long journey