The word of the day is Holloway:
The name “holloway” is derived from “hola weg,” meaning sunken road in Old English. You’re most likely to discover a holloway where the ground and the stone below are soft, such as places rich in sandstone or chalk. No one ever engineered a holloway — erosion by human feet, and horses or cattle driven alongside, combined with water then flowing through the embankments like a gully, molded the land into a tunneled road. It’s hard to date them, but most are thought to go back to Roman times and the Iron Age, although in the Middle East some are believed to stretch back to ancient Mesopotamia. They even have their own ecology, such as the spreading bellflowers that enjoy the disturbed earth.