Which element must be clearly indicated on the Survey Map or Plat?

The element that must be clearly indicated on the Survey Map or Plat is the source of reference for the north arrow. This is crucial because the north arrow provides orientation for the map, allowing users to understand the directional layout of the surveyed land. By specifying the source of reference, it ensures that anyone using the map can verify the orientation and align the survey with other plans or documents accurately.

Including the source of reference enhances the map's reliability and usability, particularly in legal or development contexts where precise orientation is important for property boundaries, easements, and other spatial relationships. It aids in ensuring that any interpretations made based on the map can be reconciled with real-world bearings and navigational aids.

In contrast, while historical context, neighboring property owner's details, and local zoning laws may be important elements in understanding the property, they are not mandatory components of a survey map or plat itself. Their inclusion would be helpful, but the primary requirement remains to establish a clear and reliable orientation through the north arrow and its reference source.