A square mile (often abbreviated as sq mi or mi²) is a unit of area used primarily in the United States and a few other countries. It is defined as the area of a square with sides that each measure one mile in length. One square mile is equal to 640 acres.
In terms of the International System of Units (SI), one square mile is approximately equal to 2.58999 square kilometers (km²).
To provide some perspective, a square mile is commonly used to describe land areas within cities, counties, and states in the United States. It's a convenient unit for measuring larger land areas, such as the size of cities or counties.
In the context of land surveying and property descriptions in the United States, a "section" refers to a specific unit of land division. It is part of the Public Land Survey System (PLSS), which was established to survey and divide land in the United States, particularly in the western and central parts of the country.