Occasionally a large boulder loomed out of the darkness, but that was all.

Two huge boulders loomed before him.

The volcano smoked above us, the air smelled of sulfur, and steam rose from the surface of the pools, where boulders loomed like the petrified dead.

The huge boulders of the breakwater loomed ahead of him, the grey stone showing white in the moonlight.

Despite the clear night the way was difficult to follow, boulders loomed to catch him unawares and break his stride.

Rocks and boulders loomed like green icebergs as we dropped closer to the valley floor.

A great boulder loomed dark before her.

A low boulder loomed suddenly ahead.

Closer and closer to each passing rock the ship inclined, until one medium-sized boulder loomed up and this didn't tilt out of the way.

Two large boulders loomed up just ahead-if he were to dash between them, the men would never be able to follow him mounted.