Tunnels and Viaducts on the A13 Motorway in Italy, by Kilometre Point

• 12entries listed
• 4.63 kmtotal length

The record table

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

How this table is compiled

The three longest entries alone account for 3.44 km of the 4.63 km on this page, which is 74 per cent of the total from 3 of 12 rows. 6 entries sit above the median and 6 at or below it, so the table is evenly weighted and not clustered at one end.

Between the longest and the tenth-longest the drop is 1.7 km, which is the part of the table that changes when a single scheme opens. Where one of these 12 lengths disagrees with an operator's own figure for Italy, the table keeps the published value and notes the difference instead of averaging the two.

Lengths for Italy are recorded in metres which is how the operators publish them and why the shortest entry here reads as 23 m and not a rounded figure. The longest entry is 78.7 times the shortest and 11.3 times the median, which is the quickest measure of how uneven the table is.

This page records the structures catalogued along the A13 in Italy, in a tunnel almanac maintained at this address since the late 1990s. The captions name 8 distinct places and structures — Romagna, Prov and RA08 among them — and those names are the index into the length tables where each is recorded with its own figure.

The route table lists 12 structures with a recorded length, giving both carriageways where the two bores differ. The material on this page is held in 4 captions rather than in running text, 26 words of it, each written against the image or row it belongs to by the compiler who put the page together.

Reading the figures

A new scheme in Italy would have to beat 1.81 km to change the head of this table, and that is the figure worth rechecking when one opens. The eighth longest is FS at 0.14 km, which is about where this record stops being about record holders and starts being about ordinary infrastructure.

The note column records 11 exits and 4 motorway connections along the route, in running order rather than by size. The table on this page runs to 16 rows and records Viaduct, Direction Padova, Direction Bologna and Notes for each of them, which is the shape the original compiler chose rather than one imposed here.

The next two longest are Adige at 1.25 km and Reno at 0.39 km. A tunnel list for Italy reads differently from a neighbouring country's: 0 of these 12 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 longest stands 0.56 km clear of the next longest, which is the margin to watch when a new scheme is announced. Laid end to end the entries on this page would run 4.63 km, which is a number with no engineering meaning but a useful sense of the scale of what is catalogued.

The twelfth longest, CER at 0.02 km, sits close enough to its neighbours that which of them ranks higher depends on how each was measured. The ten longest average 0.45 km against 0.06 km for everything below them, and that ratio is the clearest thing this table says about the distribution.