Numerous industrial narrow-gauge lines were built for peat extraction, clay extraction for brickworks and construction sites. The dominant gauge for industrial lines was 700 mm (2 ft 3+9⁄16 in), contrary to the 600 mm (1 ft 11+5⁄8 in) gauge used in neighbouring countries. Nowadays, much of this industrial rail heritage is preserved in museums or in theme parks, such as the Efteling Steam Train Company. The majority of the Dutch narrow-gauge railways were built as steam tram networks, predominantly with 750 mm (2 ft 5+1⁄2 in) and 1,067 mm (3 ft 6 in) track gauge.