across/through

[diamondcutter]

The son set out eagerly. He travelled really far, across forests and mountains. Finally, he reached the place and began to dig.

(Source: from a reading comprehension passage in the English test paper, senior high school entrance exams, Anhui province, China, 2021)

I think the preposition “across” in the second sentence should be “through”. What do you say?

 

[emsr2d2]

I don't agree. Imagine it's a map (flat). His travels took him across different topographical features. If you really want to be picky about them, you'd have to say "through forests and over mountains".