What is an alternative name for a hydrolaccolith, a mound of earth-covered ice found in the Arctic and subarctic that can reach up to 70 metres (230 ft) in height and up to 600 m (2,000 ft) in diameter?
Pingo Pingo A pingo, also called a hydrolaccolith or a bulgunniakh, is a mound of earth-covered ice found in the Arctic and subarctic that can reach up to in height and up to in diameter. The term originated as the Inuvialuktun word for a small hill. The plural form is "pingos". The term is also used for depressions, often water filled, formed by the melting of ice at the end of the last glaciation. A pingo is a periglacial landform, which is defined as a nonglacial landform or process linked to colder climates. "Periglacial" suggests an environment located on the margin
2 ft and 600 mm gauge railways 2 ft gauge railways in South Africa and currently some surviving locomotives reside in Wales on the gauge Welsh Highland Railway and the gauge Brecon Mountain Railway. 2 ft and 600 mm gauge railways Two foot and 600 mm gauge railways are narrow gauge railways with track gauges of and , respectively. Railways with similar, less common track gauges, such as and , are grouped with 2 ft and 600 mm gauge railways. Most of these lines are tourist lines, which are often heritage railways or industrial lines, such as the Festiniog Railway in Wales and the Cripple Creek and