Sand shifts under your boot while you toil up the dune. It's not so bad while you're down in the salt grass: wiry growth gives some purchase. The slope picks up and the grains tumble down, though, slight purchase turning your ankle as you step in the prints of all the boots before, and every step takes the effort of three.
The top is worth it. Footstep-dimpled as well, but from here you can see the sea, and the white-edged dimples across the waves are not the marks of people who have been there before.