A hectare is a measure of area. One hectare is 10 000 square
metres, equivalent to the area of a square 100 metres by 100
metres. A hectare is approximately 2 ½ acres, about
the size of a rugby pitch.
A square 100 m on each side is one hectare, the most common
and convenient SI area multiple used in the surveying profession
for day to day legal documents such as land deeds, mortgage
surveys, town planning, environmental protection, and other
necessary property considerations under the law.
kilometers are often too large to work with conveniently,
and square meters are similarly too small.