Lat/long for EILLocation

An instance of EILLocation can store longitude and latitude. What point of the shape does this real world coordinates correspond to? Like: Are these coordinates the center of the shape? Or the coordinates of the First EILPoint given? Or any other point?

Furthermore: Do the conversion routines found in the sdk like calculatePicturePointFromRealPoint:(EILPoint *)realPoint take these coordinates int o account?