A more thorough explanation:

Perambulatione facienda is a legal term that refers to a writ issued by a court to settle a boundary dispute between two adjacent towns or lordships. The writ orders the sheriff to go with 12 knights of the county to walk around the disputed area and determine the proper boundary.

For example, if two towns were arguing over the exact location of their shared boundary, they could request a perambulatione facienda writ from the court. The sheriff and 12 knights would then walk around the disputed area, examining the land and any markers or boundaries that had been previously established. Based on their observations, they would determine the proper boundary and settle the dispute.

Another example might be a dispute between two lordships over the ownership of a particular piece of land. The perambulatione facienda writ would be used to determine which lordship had the rightful claim to the land by walking around the area and examining any relevant evidence.

These examples illustrate how the perambulatione facienda writ was used in medieval times to settle boundary disputes. By physically walking around the disputed area and examining the evidence, the sheriff and knights were able to make an informed decision about the proper boundary and resolve the dispute.