Symbol: **mi²**

Unit System: Imperial

Unit System: Imperial

The square mile is a unit of area and is an imperial unit with the symbol mi².

One square mile is equal in area to a square with edges one mile in length.

The Romans established the square mile; computed through a system of feet, paces and marches. The square mile's existence still remains in some places; for example "The Square Mile" is a term often used to describe the very centre of London in the UK (which just so happens to measure 1mi²).