They piled up here after drifting in across a prehistoric sea from God knows where.

Miles from the coast, Cheshire plants cope with the remains of a salty prehistoric sea.

Our countdown of the seven prehistoric seas you'd least like to take a dip in.

Eventually the mosasaurs took over the Pliosaur niche in the prehistoric seas.

It is often seen in documentaries about prehistoric seas.

The sandstone of the cliffs was the remnant of the prehistoric sea that covered the Midwest approximately 300 million years ago.

I suppose the first invertebrates who crawled up out of the prehistoric seas felt just as we do-hating every minute of it.

The Stillwater wetlands are the vestige of a prehistoric sea that once spread across northwestern Nevada and into California.

It was deposited on the floor of a shallow, prehistoric sea that covered much of western North America about 350 million years ago.

The soil in this part of the state comes from when a prehistoric sea dried up and left sediment in its place.