|boundary = marker|
|A physical marker that identifies a boundary|
|Used on these elements|
|Status: in use|
|Tools for this tag|
A, border marker, boundary stone, border stone, boundary tree, is a robust physical marker that identifies the start of a land boundary or the change in a boundary, especially a change in direction of a boundary.
Boundary markers, traditionally, were often made of stone, but later many have been made with concrete or a mixture of materials. They are typically placed at a notable or especially visible point. Many are inscribed with relevant information such as the abbreviation of the boundary holder and often a date.
The word "Boundary marker" is 'all-encompassing', because a boundary_stone is a boundary_marker, but not all boundary_markers are in stone. Also, there are boundary trees.
How to map
If a boundary marker is historic, one can simply add historic=yes .