Yeah, very poor contrast and readability. Just about everything on the map is of medium intensity and high saturation. It's hard to read even with normal colour vision.

"Here lies the Great hills of sand. Wander in not, for many never return."

You've got a plurality agreement problem, some odd capitalization, and the language is just a bit ungainly in places. You might try something more like:

"Here stand The Great Hills of Sand. Those who brave them seldom return."