# Square mile

A

**square mile** (symbol

**mi²**) is an

imperial unit which is the

area of a

square whose side is one

mile (or 5,280

feet). A square mile is equal to 27,878,400 square feet, 640

acres, or roughly 2½ square kilometers (2.589988 km², to be more exact).

*See also*: Conversion of units

In

England,

**the Square Mile** is a traditional name for the

City of London.