Underground excavation is a type of mining that involves digging below the surface of the earth. It is typically done to extract minerals, metals, and other resources. The most common methods of underground excavation are MINE, SHAFT, stope, DIG, TRENCH, and BURROW. A MINE is an excavation in the ground for the purpose of extracting coal, ores, or other valuable minerals. A SHAFT is a vertical or inclined excavation used to access a mineral deposit. A stope is an underground excavation created by removing ore from a MINE. Digging is the process of excavating soil or rock with tools such as shovels or picks. A TRENCH is a long, narrow excavation made in the ground. Finally, a BURROW is an excavation made by an animal, such as a rabbit, for shelter or habitation.