He sits and rests his head on a smooth boulder.

The pool was surrounded on two sides by round, smooth boulders.

Each of the huge, smooth boulders tested his injured leg to its limit.

Dwight scrambled backwards until his back encountered the cold, smooth boulder.

Halfway down the pass is a camping ground, with a river pool set amid smooth boulders.

Upstream, a still pool showed black among smooth boulders.

I turned downstream and followed it, jogging over the smooth boulders that lined its banks.

During these stages smooth boulders from the river were incorporated into the mound, possibly to help stabilize the shape.

Leaning out, he hurled it at what looked like a smooth boulder sticking out of the water.

Gigantic muscles in its legs and flanks stood out like smooth scaly boulders.