Meanings of dim mountains in English

The sun was just about to set, behind dim mountains, many miles distant across the marsh.

Beyond the blue of the yet restless waters rose dim mountains tipped with snow, like some Mediterranean seascape.

Ahead the tracks arrowed through the endless fields of waving grain; dim mountains, old teeth, floated in the western clouds.

They interspersed the work with long, restful moments when they looked afar down the vast reaches and smoky shingles to the line of dim mountains.