Square kilometre (International spelling as used by the International Bureau of Weights and Measures) or square kilometer (American spelling), symbol km2, is a multiple of the square metre, the SI unit of area or surface area.
1 km2 is equal to:
1,000,000 square metres (m2)
100 hectares (ha)
It is also approximately equal to:
0.3861 square miles
247.1 acres
Conversely:
1 m2 = 0.000001 (10−6) km2
1 hectare = 0.01 (10−2) km2
1 square mile = 2.5899km2
1 acre = about 0.004047km2
The symbol "km2" means (km)2, square kilometre or kilometre squared and not k(m2), kilo–square metre. For example, 3 km2 is equal to 3×(1,000m)2 = 3,000,000 m2, not 3,000 m2.
Topographical map grids are worked out in metres, with the grid lines being 1,000 metres apart.
1:100,000 maps are divided into squares representing 1 km2, each square on the map being one square centimetre in area and representing 1 km2 on the surface of the earth.
For 1:50,000 maps, the grid lines are 2 cm apart. Each square on the map is 2 cm by 2 cm (4 cm2) and represents 1 km2 on the surface of the earth.
For 1:25,000 maps, the grid lines are 4 cm apart. Each square on the map is 4 cm by 4 cm (16 cm2) and represents 1 km2 on the surface of the earth.
In each case, the grid lines enclose one square kilometre.
The area enclosed by the walls of many European medieval cities were about one square kilometre. These walls are often either still standing or the route they followed is still clearly visible, such as in Brussels, where the wall has been replaced by a ring road, or in Frankfurt, where the wall has been replaced by gardens. The approximate area of the old walled cities can often be worked out by fitting the course of the wall to a rectangle or an oval (ellipse). Examples include
Delft, Netherlands (See map alongside) 52°0′54″N 4°21′34″E
The walled city of Delft was approximately rectangular.
Lucca (Italy) 43°50′38″N 10°30′2″E
The medieval city is roughly rectangular with rounded north-east and north-west corners.
Brugge (Belgium) 51°12′39″N 3°13′28″E
The medieval city of Brugge, a major centre in Flanders, was roughly oval or elliptical in shape with the longer or semi-major axis running north and south.
Chester United Kingdom 53°12′1″N 2°52′45″W
Chester is one of the smaller English cities that has a near-intact city wall.
Parks come in all sizes; a few are almost exactly one square kilometre in area. Here are some examples:
Riverside Country Park, UK.
Brierley Forest Park, UK.
Rio de Los Angeles State Park, California, USA
Jones County Central Park, Iowa, USA.
Kiest Park, Dallas, Texas, USA
Hole-in-the-Wall Park & Campground, Grand Manan Island, Bay of Fundy, New Brunswick, Canada
Downing Provincial Park, British Columbia, Canada
Citadel Park, Poznan, Poland
Sydney Olympic Park, Sydney, Australia, contains 1 square kilometre of wetlands and waterways.
Using the figures published by golf course architects Crafter and Mogford, a course should have a fairway width of 120 metres and 40 metres clear beyond the hole. Assuming a 6,000 metres (6,600 yd) 18-hole course, an area of 80 hectares (0.8 square kilometre) needs to be allocated for the course itself. Examples of golf courses that are about one square kilometre include:
Manchester Golf Club, UK
Northop Country Park, Wales, UK
The Trophy Club, Lebanon, Indiana, US
Qingdao International Country Golf Course, Qingdao, Shandong, China
Arabian Ranches Golf Club, Dubai
Sharm el Sheikh Golf Courses: Sharm el Sheikh, South Sinai, Egypt
Belmont Golf Club, Lake Macquarie, NSW, Australia
The Old City of Jerusalem is almost 1 square kilometre in area.
Milton Science Park, Oxfordshire, UK.
Mielec Industrial Park, Mielec, Poland
The Guildford Campus of Guildford Grammar School, South Guildford, Western Australia
Sardar Vallabhbhai National Institute of Technology (SVNIT), Surat, India
Île aux Cerfs Island, near the east coast of Mauritius.
Peng Chau Island, Hong Kong
