St. Gotthard / San Gottardo vs Laerdal: length, opening date, class

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Side by side

St. Gotthard / San Gottardo is recorded on data/tun10.html and Laerdal on data/tun10.html, compiled to the same convention, which is what makes the two figures comparable at all.

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

How this table is compiled

The median road tunnel in this archive measures 12.46 km, so both entries here are well clear of the ordinary case and the comparison is between two outliers rather than two typical crossings. Tunnels are regularly repurposed, and the mode a bore was built for is not always the mode it now carries.

A 20-year gap spans real changes in ventilation, escape provision and excavation method, so the two were not built to the same standard. The 1980s account for 25 entries in this archive, and St. Gotthard / San Gottardo is one of them, which is the context a single opening date does not carry on its own.

At over twenty kilometres Laerdal sits in the small group of bores long enough to need intermediate ventilation and a full escape regime. This archive separates 4 classes of structure and both entries here are indexed under road tunnel, which decides the table each is ranked in and the convention its length was measured by.

That gap is about 31 per cent of the longer bore, which is the figure worth holding on to rather than the raw metres. Driven end to end the two would run 41.45 km, which is the figure to hold against the 24.51 km of the longest single road tunnel in the record.

St. Gotthard / San Gottardo and Laerdal are compared here on the figures this archive records for each, taken from the same sources and the same measurement convention. 18 other structures in this record opened within two years of Laerdal, which is the cohort it was designed alongside and the fairer comparison for how it was built.

Reading the figures

Laerdal is the longer of the two at 24.51 km, ahead of St. Gotthard / San Gottardo at 16.94 km, a difference of 7.57 km. Counting every class, 29 recorded structures fall between these two by length; the comparison is a window on that part of the record rather than a gap in it.

Across every class this archive records, Laerdal stands 20th by length and St. Gotthard / San Gottardo 50th, so the pair sits inside the top 50 of 244 structures. Both pass ten kilometres, which 161 of the 244 structures recorded here manage, so this is a comparison inside a small group rather than across the field.

St. Gotthard / San Gottardo opened in 1980 and Laerdal 20 years later in 2000, and that gap usually matters more than the length difference. Laerdal is the longest road tunnel in this archive, which makes this comparison one against the record itself rather than two entries below it. Sources are named on each structure's own table.

4 recorded road tunnels fall between them by length, the nearest being Tianshan Shengli at 22.13 km. Motorway crossings are usually twinned, and the second bore is often driven decades after the first. Ventilation shafts allow a longer bore to be driven, and their absence is often what caps a tunnel's length rather than money or ambition.

19 recorded structures are longer than Laerdal, the nearest of them Pajares Base at 24.6 km. Water under pressure delays a heading more reliably than distance does, and it appears in no ranking. A national administration publishes what it maintains, so a crossing that changes owner can move between lists.