deep excavation
- trenchLong narrow excavation
- pitFruit's hard seed
- digUnearth by shoveling
- undergroundBelow ground or countercultural
- foundationUnderlying support structure
shaft · earth · soil · bedrock · tunnel · crater · cavity · chasm · drilling · bore · groundwater · construction · mud · walls · shoring · collapse · layers · sediment
vertical direction
deep excavationtall structure
building up · elevation · skyscraper · landfill · superstructure