Track geometry

Track gauge
By transport mode
Rapid transit Tram Miniature Scale model
By size (list)
Minimum   Fifteen inch 381 mm (15 in)   Narrow   600 mm 600 mm (1 ft 11+5⁄8 in) Two foot 610 mm (2 ft) Two foot three inch 686 mm (2 ft 3 in)   750 mm 750 mm (2 ft 5+1⁄2 in) Bosnian gauge 760 mm (2 ft 5+15⁄16 in) Two foot six inch 762 mm (2 ft 6 in)   Swedish three foot 891 mm (2 ft 11+3⁄32 in) 900 mm 900 mm (2 ft 11+7⁄16 in) Three foot 914 mm (3 ft) Italian metre 950 mm (3 ft1+13⁄32 in)   Metre 1,000 mm (3 ft 3+3⁄8 in)   Three foot six inch 1,067 mm (3 ft 6 in)   Four foot 1,219 mm (4 ft)   Four foot six inch 1,372 mm (4 ft 6 in)   1432 mm 1,432 mm (4 ft 8+3⁄8 in)   Standard 1,435 mm (4 ft 8+1⁄2 in)   Broad   Italian broad gauge 1,445 mm (4 ft 8+7⁄8 in) Dresden gauge 1,450 mm (4 ft 9+3⁄32 in)   Leipzig gauge 1,458 mm (4 ft 9+13⁄32 in)   Toronto gauge 1,495 mm (4 ft 10+7⁄8 in)   1520 mm 1,520 mm (4 ft 11+27⁄32 in) Five foot 1,524 mm (5 ft)   Pennsylvania gauge 1,581 mm (5 ft 2+1⁄4 in) Pennsylvania gauge 1,588 mm (5 ft 2+1⁄2 in) Five foot three inch 1,600 mm (5 ft 3 in)   Baltimore gauge 1,638 mm (5 ft 4+1⁄2 in)   Iberian gauge 1,668 mm (5 ft 5+21⁄32 in) Five foot six inch 1,676 mm (5 ft 6 in)   Six foot 1,829 mm (6 ft)   Brunel 2,140 mm (7 ft 1⁄4 in)   Breitspurbahn 3,000 mm (9 ft 101⁄8 in)
Change of gauge
Bogie exchange Break of gauge Dual gauge Conversion list Variable gauge
By location
North America South America Europe Australia

Track geometry is concerned with the properties and relations of points, lines, curves, and surfaces^[1] in the three-dimensional positioning of railroad track. The term is also applied to measurements used in design, construction and maintenance of track. Track geometry involves standards, speed limits and other regulations in the areas of track gauge, alignment, elevation, curvature and track surface.^{[2][failed verification]} Standards are usually separately expressed for horizontal and vertical layouts although track geometry is three-dimensional.