Unit Definition (feet [international, U.S.])
The human foot has long been a standard unit for the measurement of length. Over history this size has varied from region to region and there is some discrepancy as to an exact standard or origin of the standard measurement for feet that we use today. In England, the Roman foot was replaced after the fall of Rome by the natural foot. The modern foot (1/3 yard or about 30.48 centimeters) did not appear until after the Norman conquest of 1066. It may be an innovation of Henry I, who reigned from 1100 to 1135. Later in the 1100's a foot of modern length, the "foot of St. Paul's," was inscribed on the base of a column of St. Paul's Church in London.

Unit Definition (mile [international])
The mile is one of the most common measurements of distance. It originates from the Latin word for 1000, 'mille'. Originally a mile was the distance a Roman legion could march in 1000 paces. In medieval Britain, several mile units were used, including the modern mile defined as 8 furlongs (1609 meters). Note that French, Scottish and Irish miles varied from the English. In 1592, Parliament defined the statute mile to be 8 furlongs or 1609.344 meters.