A rod is a unit of length used in some systems of measurement, primarily in the United States and the United Kingdom. In the U.S. customary system, one rod is equal to 16.5 feet or 5.0292 meters. It is also equivalent to 1/4 of a chain, which is another traditional unit of length.
Rods were historically used for land measurement, particularly in surveying and real estate. In some cases, you may still come across the use of rods in property descriptions, especially in rural or agricultural areas. However, the use of the rod as a standard unit of measurement has become less common in favor of more standardized systems like the metric system or the U.S. customary system based on feet and yards.
The "vara castellana" is a historical unit of length that was used in Spain. It was commonly used for land measurement and other purposes in various regions of Spain, especially in the Castile region, which is why it is called the "castellana" vara. The exact length of the vara castellana could vary by region and historical period.
In general, the vara castellana was approximately 835.9 millimeters or about 32.91 inches in length. However, variations existed, and in different parts of Spain and at different times in history, the length of the vara castellana could differ slightly.
Like many historical units of measurement, the vara castellana has largely been replaced by more standardized and modern systems of measurement, such as the metric system. In contemporary Spain, the metric system is the standard for length measurement.