Puerto Rican units of measurement

Several units of measurements are used in Puerto Rico. The metric system has been compulsory since 1860 in Puerto Rico. One notable exception are public roadway speed limits: whereas distances are shown in the metric system (kilometers), speed limits are posted in the United States customary units (miles per hour). 
System before metric system.
Several units were used before metric adoption. These units were older Spanish units.
Area.
Several units were used to measure area. Among them were the "cuerda" and the "caballería".
"Cuerda".
One cuerda is equal to 2250 vara2(1572 m2). It continues to be an official unit of land measure in Puerto Rico today (2019).
"Caballería".
This was a unit of land measurement in the Spanish Viceroyalties in the Americas during the times of the Spanish Empire in the 16th through 19th centuries Puerto Rico. Widely use then, it was equivalent to . This unit of measure is now (2019) obsolete.