Subsea Road Tunnels in Norway, with Length, Maximum Depth and Gradient

• 43entries listed
• 26.66 kmlongest bore
• 1982–2019openings span
• 215.59 kmtotal length

The record table

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

How this table is compiled

Where one of these 43 lengths disagrees with an operator's own figure for Norway, the table keeps the published value and notes the difference instead of averaging the two. The longest entry is 53.3 times the shortest and 7.1 times the median, which is the quickest measure of how uneven the table is.

Lengths for Norway are recorded in metres which is how the operators publish them and why the shortest entry here reads as 500 m and not a rounded figure. The eighth longest is Nordkapp at 6.88 km, which is about where this record stops being about record holders and starts being about ordinary infrastructure.

A new scheme in Norway would have to beat 26.66 km to change the head of this table, and that is the figure worth rechecking when one opens. The dated entries fall across 21 different years, which is a rough measure of whether this was a sustained programme or a handful of separate schemes.

Dated entries run from 1982 to 2019, and the busiest decade is the 1990s with 11 recorded openings. The table on this page runs to 36 rows and records Date of opening, Tunnel, County, Length and Max. depth for each of them, which is the shape the original compiler chose rather than one imposed here.

16 of the 43 measured entries exceed five kilometres, and those are the ones that carry a full ventilation and escape regime. Laid end to end the entries on this page would run 215.59 km, which is a number with no engineering meaning but a useful sense of the scale of what is catalogued.

Reading the figures

The next two longest are Ryfylke at 14.1 km and Hadselfjorden at 9 km. A tunnel list for Norway reads differently from a neighbouring country's: 30 of these 43 structures pass three kilometres, and the same journey time is bought with one long bore in one country and a dozen short ones in another.

The dated entries carry 21 distinct opening years across 37 years, and the median opening year is 2000. Read down the length column, the 35 values run from 500 m to 14 100 m with a midpoint at 3 751 m; the spread rather than the maximum is what says how uneven this set is.

The ten longest average 10.37 km against 3.39 km for everything below them, and that ratio is the clearest thing this table says about the distribution. The tunnel column names 36 distinct entries on this page, Vardø and Ellingsøy among them, each traceable to the operator or administration record it was taken from.

The table below lists 43 entries with a recorded length, each giving a name, a length in metres and, where documented, the year of opening. The entries sum to roughly 215.59 km of bore, an average of about 5.01 km each, though that average describes no actual row.

15 of the 43 entries fall within a quarter of the median length, which is how tightly this particular list clusters around its typical structure. 7 of the dated entries opened from 2010 onwards, which shows how much of what is listed here is recent construction and not historic work.