In other places, a depression had been worn into the soft sandstone to show the way.
In some areas, the limestone is capped with a soft sandstone.
Built of soft sandstone, the tower is very weathered, and has been partially refaced.
There we saw prehistoric writing on rocks striped with very soft sandstone - yellow, red, blue, green.
Wind and rain have also sculpted the soft sandstone over millions of years.
For the next year, workers dug in the soft sandstone beneath the thin layer of limestone that forms the river's bed.
Many gardens built on a slope include a small wine cellar excavated out of the soft sandstone.
Bowles Rocks is made of a relatively soft sandstone, formed 130 to 140 million years ago.
The valley was also blessed with large deposits of soft sandstone for building.
Do not use a wire brush, which will damage the soft sandstone.