Jinpingshan vs St. Gotthard / San Gottardo: length and opening date

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Side by side

Jinpingshan is recorded on data/tun10.html and St. Gotthard / San Gottardo 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

Neither holds the record: Laerdal at 24.51 km is the longest road tunnel recorded here, 7.01 km ahead of Jinpingshan. 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.

A 31-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.

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. Where a structure has been lengthened by a later extension the current figure is the one recorded, with the original noted alongside it.

That gap is about 3 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 34.45 km, which is the figure to hold against the 24.51 km of the longest single road tunnel in the record.

Jinpingshan and St. Gotthard / San Gottardo are compared here on the figures this archive records for each, taken from the same sources and the same measurement convention. 58 other structures in this record opened within two years of Jinpingshan, which is the cohort it was designed alongside and the fairer comparison for how it was built.

Reading the figures

Jinpingshan is the longer of the two at 17.5 km, ahead of St. Gotthard / San Gottardo at 16.94 km, a difference of 0.56 km. Counting every class, 1 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, Jinpingshan stands 48th 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 Jinpingshan 31 years later in 2011, and that gap usually matters more than the length difference. Cross-border schemes require two states to fund the same hole at the same time, which is why they take decades. Figures are checked against one another where they differ.

Jinpingshan was designed under the modern regime, with cross-passage spacing and emergency ventilation specified from the outset. Traffic volumes are excluded for the same reason, and because they date far faster than the structures themselves. Fixed links change settlement patterns, so the traffic a crossing carries later is not the traffic that justified it.

47 recorded structures are longer than Jinpingshan, the nearest of them Gaoganshan at 17.61 km. Structures still under construction cannot hold a record here, and are listed separately until they carry traffic. The most useful sources are the least accessible: inspection records and commissioning documents rather than announcements. Portals and approaches are counted consistently.