The highest railways in the world, ranked by height above sea level

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The record table

Ranked by height above sea level at the highest point of the line. Altitude and length are unrelated records: a short line over a pass can reach far higher than a long base tunnel driven low through the same range.

How this archive measures: lengths, bores, dates and ordering

How this table is compiled

Passenger carriages on the Tibetan line are pressurised and supplied with oxygen, which is a rail engineering problem more usually found in aviation. Altitude and length pull in opposite directions: a base tunnel exists precisely to avoid height, so the longest tunnels are among the lowest. Every figure below is traceable to a named source.

The note column is worth reading before the number. Where a record is contested the table states both the figure and the reason for the dispute, instead of picking a winner silently. Opening dates refer to the date traffic was admitted, not to the completion of construction, which normally falls a year or two earlier.

Roughly 960 kilometres of that line runs above 4 000 metres, which is what makes its engineering problem permafrost rather than gradient. Opening year is given, not the year of contract award. Corrections have historically arrived by letter rather than by form, and that is still the way most errors in it have been found.

The engineering problem at height is not gradient or ventilation but permafrost, oxygen and the behaviour of concrete in extreme cold. Renaming is common on long routes, so a designation in the table reflects the name in use at the time of recording. Ranking is by the figure named in the header, nothing else.

Before it opened in 2006 the record had stood in the Peruvian Andes for over a century, on the Central Railway. Comparing one country's figure against a neighbour's is more informative than reading either alone, because designation practice differs sharply across borders. A record is a claim about a definition as much as a measurement.

Reading the figures

This table records the highest railways in the world, part of an infrastructure archive kept here since the late 1990s. Geology and terrain decide cost and programme far more than distance does, on a road as much as in a bore. Superlatives attract dispute because they are the figures most often quoted without their qualifications attached.

Track laid on permafrost has to be kept frozen, so parts of the line are actively cooled rather than insulated. The Peruvian record stood from 1893 until 2006, one of the longest-held records in this archive. A record table is a snapshot with a date on it, which is the only honest way to publish one.

The archive began as a private compilation and grew through correspondence with engineers and administrations in more than twenty countries. A superlative is only as good as its definition, and most disputes in this field are definitional rather than factual. Metres are used for structures and kilometres for routes, matching the units the responsible administrations publish.

Altitude is the one record class in this archive where length is actively unhelpful as a proxy. Reading the note column before the figure is usually the faster route to understanding what a record actually claims. A projected opening date is a forecast, and on schemes of this size forecasts have historically slipped by years.

La Galera remains the highest railway tunnel outside Tibet, and was driven in 1893 through the Meiggs mountain. Structures still under construction appear on their class tables but cannot hold a record until they carry traffic. Cost figures are omitted throughout, because currency, inflation and differing project scope make them close to meaningless in comparison.