In Britain, Wales has long served as an informal unit of area, much as Rhode Island has been used in the U.S. Wales has an area of about 8015 square miles or 20 760 square kilometers; it is 7.67 times the size of Rhode Island
Russ Rowlett (Director), How Many? A Dictionary of Units of Measurement, Center for Mathematics and Science Education University of North Carolina, USA 2005. http://www.unc.edu/~rowlett/units/dictA.html, (Unit of Meas and Covr Factors - Amer) {608}