Our distances are not driving distances, but are calculated as a 'straight-line' distance that begins in Thompson. A straight line distance ignores obstructions like rivers, canyons, lakes, et cetera - it's truly a line from Point A (ie- Thompson) to Point B.
Our distance measurements begin at a specific point in Thompson. The point that we are using is located at these GPS coordinates - Latitude: 35.0051, Longitude: -90.3390 [Map]. In this case, the coordinates for Thompson have been provided by the Geographic Names Information System (GNIS).