Kilometre per square kilometre is an

SI derived unit SI derived units are units of measurement derived from the seven base units specified by the International System of Units (SI). They can be expressed as a product (or ratio) of one or more of the base units, possibly scaled by an appropriate po ...

reciprocal length Reciprocal length or inverse length is a quantity or measurement used in several branches of science and mathematics. As the reciprocal of length, common units used for this measurement include the reciprocal metre or inverse metre (symbol: m− ...

used for measurement of density of a

linear Linearity is the property of a mathematical relationship (''function'') that can be graphically represented as a straight line. Linearity is closely related to '' proportionality''. Examples in physics include rectilinear motion, the linear r ...

feature in an

area Area is the quantity that expresses the extent of a region on the plane or on a curved surface. The area of a plane region or ''plane area'' refers to the area of a shape A shape or figure is a graphics, graphical representation of an obje ...

. It is used to measure, for example,

drainage density Drainage density is a quantity used to describe physical parameters of a drainage basin. First described by Robert E. Horton, drainage density is defined as the total length of channel in a drainage basin divided by the total area, represented by t ...

road density A road is a linear way for the conveyance of traffic that mostly has an improved surface for use by vehicles (motorized and non-motorized) and pedestrians. Unlike streets, the main function of roads is transportation. There are many types of ...

(i.e. kilometres of road per square kilometre of land).

Transport density in the European Union

In the European Union, kilometre per square kilometre is the unit of measure of transport network density.

Motorway density

According to Europa.eu, Usually, the densest motorway networks are found around capital cities and other big cities, in large industrial conurbations and around major seaports. The regions with the higher motorway density are: * the German city-state regions of Bremen, Hamburg and Berlin (186 km, 107 km and 86 km per thousand km²) * Düsseldorf (121 km per thousand km²) * Saarland (93 km per thousand km²).https://ec.europa.eu/eurostat/documents/3217494/5784025/KS-HA-13-001-10-EN.PDF/28921853-f4a0-4f2f-80d3-f7d1a9b4021c * the north-western part of England (138 km per thousand km² in Greater Manchester) * the West Midlands of England (90 km per thousand km²); * the Randstad region in the west of the Netherlands (where densities reached 129 km, 128 km and 106 km per thousand km² in South Holland, Utrecht and North Holland respectively) * the southern Dutch regions of Limburg and North Brabant (100 km and 99 km per thousand km² respectively). Many cities are rounded by a motorway ring, so the density metric is dependent on the size of the city: * Lisbon (222 km per thousand km², in 2004), * Vienna (109 km per thousand km²) * Comunidad de Madrid (98 km per thousand km²)

Rail density

EU-15 had 48.3 km of railways per 1,000 square kilometres in 2000), more than in the United States (30.6 km/1000 km² in 1999, including Alaska and Hawaii and inland waters) but less than in Japan (53.5 km/1000 km² in 1999). For rail networks, in Europe, the highest network density can be found in the Czech Republic, Belgium, Luxembourg and Germany (above 100 km/1000 km²), followed by the Netherlands, Hungary, Austria, Slovakia, the United Kingdom and Poland (65–86 km/1000 km²). At the lower end of the range are Turkey, Norway, Finland and Greece, with values of 20 km/1000 km² and below.

References

Geomorphology Length {{measurement-stub