An arpent (French pronunciation: [aʁpɑ̃]) is a unit of length and a unit of area. It is a pre-metric French unit based on the Roman actus. It is used in Quebec as well as in some areas of the United States that were part of French Louisiana.
Unit of length 
|58.471 m||5,847.1 cm|
|US customary / Imperial units|
|63.945 yd||191.83 ft|
There were various standard arpents. The most common ones were of 180 French feet, used in French North America, and 220 French feet, used in Paris.
1 arpent = 180 French feet (of approximately 32 centimetres) = about 192 English feet = about 58.47 metres
Unit of area 
- Historically, in North America, 1 (square) arpent = 32,400 French square feet = about 3419 square metres
- In Louisiana, Mississippi, Alabama, and Florida, the official conversion is 1 arpent = 0.84628-acre (3,424.77365-square-metre)
- In Arkansas and Missouri, the official conversion is 1 arpent = 0.8507-acre (3,442.66076-square-metre) square metres
Arpents in U.S. land descriptions (Louisiana) 
In Louisiana, parcels of land known as arpent sections or French arpent land grants also pre-date the Public Land Survey System (PLSS), but are treated as PLSS sections. An arpent is a French measurement of approximately 192 feet (59 m), and a square arpent (also referred to as an arpent) is about 0.84 acres (3,400 m2).
French arpent land divisions are long narrow parcels of land usually found along the navigable streams of southern Louisiana, and also found along major waterways in other areas. This system of land subdivision was begun by French settlers in the 18th century, according to typical French practice at the time and was continued by both the Spanish and by the American government after the acquisition of the Louisiana Purchase. A typical French arpent land division is 2 to 4 arpents wide along the river by 40 to 60 arpents deep, while the Spanish arpent land divisions tend to be 6 to 8 arpents wide by 40 arpents deep.
This method of land division provided each land-owner with river frontage as well as land suitable for cultivation and habitation. These areas are given numbers just like standard sections, although the section numbers frequently exceed the normal upper limit of 36.
See also 
- Units of measurement in France before the French Revolution
- Voltaire famously dismissed Canada as Quelques arpents de neige, "some acres of snow".
- Weights and Measures Act (R.S. 1985)