Convert from mile [Roman, ancient] to ridge

Unit Definition (mile [Roman, ancient])
A non metric unit of length; a statute mile, used for distances over land, is defined as 5280 ft.; a nautical mile, used for distances along the surface of the oceans, is defined as one minute of arc measured along the equator, which equals 6080.27 fit or 1.1516 statute miles.

Unit Definition (ridge)
The ridge is a traditional Welsh unit of distance equal to 3 leaps or 20 feet 3 inches (6.1722 meters).