Beautify Cave Wall
Beautify Cave Wall is a command players can use to have citizens redesign the edges of cave walls that were previously dug out. When this command is selected, the player can make a selection by clicking and dragging around cave walls, but only cave walls.
When cave walls are dug out, the walls will have a rugged, rough look to them, but once they are beautified with the command, the walls appear much smoother and more aesthetically pleasing to both the eyes of the player, and the citizens who see them.
In-game description
"Polishes cave walls and makes them more appealing to your subjects."