Metes refers to the straight line between two points. Each point is a monument. This includes the curb of a road, a boulder, tree line or any other element that would end a straight line. Surveyors refer to these as bounds. If there are no natural bounds, the surveyor creates one by driving a stake into the ground.
Seem like the metes and bounds system has some fuzzy math? It does. Most property owners cannot clearly identify where their property lines lie. And what about rural areas? The owner of a 25 acre slab of land may not be concerned with every square-foot, so long as they maintain rights to their land. It’s far more common that the legal description of a property’s boundaries, which clearly entails a property’s boundary lines, are only well known when there is a dispute.