In geology, bedrock is solid rock that lies under loose material (regolith) within the crust of Earth or another terrestrial planet.
https://github.com/davepinch/pinchy.cc/blob/master/content/topics/geology/rocks/bedrock/wikipedia/en.wikipedia.org.md
the texture of the cityscape of Seattle is dominated by concrete, and the freeway itself appears like a dry concrete riverbed that flows through the city Angela Danadjieva, designer of Freeway Park
The various kinds of broken and weathered rock material, such as soil and subsoil, that may overlie the bedrock are known as regolith.