What are landmarks that provide a stable point of reference for surveys called?

Landmarks that provide a stable point of reference for surveys are called monuments. These monuments serve as fixed points that surveyors can use to define property boundaries and conduct land surveys accurately. They are often established through various methods, including physical structures like concrete markers, stones, or metal posts, and can also be natural landmarks, such as trees or hills, which have been designated for this purpose.

Monuments are crucial in legal property descriptions and surveys because they help establish the accurate location of land and its boundaries over time. Their permanence ensures that property lines can be referenced accurately, which is essential for resolving disputes and ensuring clear ownership.

The other options relate to different concepts in land ownership and surveying. Boundaries refer to the lines that delineate the extent of a property but do not represent the physical markers themselves. Markers can signify specific points but may not have the permanence or legal recognition that monuments do. Land plots refer to individual parcels of land but do not denote the fixed points used in the surveying process.