2 ft 6 in gauge railways

2 ft 6 in (762 mm) gauge railways are narrow gauge railways with track gauge of 2 ft 6 in (762 mm). That gauge was particularly promoted by Thomas Hall and Everard Calthrop during the second half of the nineteenth century, especially in colonies of the British Empire.

Several Bosnian-gauge railways with 760 mm (2 ft 5+15⁄16 in) are found in south-eastern Europe. 760 mm (29.92 in) is well within engineering tolerance of 762 mm (30.0 in).