CATDIS

1. distance mark not physically installed: a point at which a distance from an origin along a feature is given for information, bu t at which no specific marker exists.
2. visible mark, pole: a point at which a distance from an origin along a feature is given for information and which is marked by a pole.
3. visible mark, board: a point at which a distance from an origin along a feature is given for information and which is marked by a board.
4. visible mark, unknown shape: a point at which a distance from an origin along a feature is given for information and which is physically marked, but the shape of the mark is not known or not given.