Minimum-gauge railway
Minimum-gauge railways are railways with track gauges smaller than those of narrow-gauge railways, primarily designed for light, industrial, or tourist transportation. The most common gauges for minimum-gauge railways include: 15 in (381 mm) 400 mm (15+3⁄4 in) 16 in (406 mm) 18 in (457 mm) 19 in (483 mm) 500 mm (19+3⁄4 in) 20 in (508 mm) These railways have been developed for applications such as estate transport, mining, agriculture, and amusement parks, offering an economical and adaptable solution for restricted environments.