Tunnels and Viaducts on the A27 Motorway in Italy, by Kilometre Point

• 42entries listed
• 3.79 kmlongest bore
• 40.19 kmtotal length

The record table

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

How this table is compiled

The 57 entries are grouped on the page under 5 headings — future connection pedemontana veneta toll highway (prj) (50), connection a4 torino – trieste (3), prov.tv-ve (2), exit casale sul sile (1) and exit macchietto - pian de l'abate (1) — a classification the table carries as section breaks rather than as a column of its own.

The route table lists 42 structures with a recorded length, giving both carriageways where the two bores differ. The table on this page runs to 57 rows and records Tunnel / Viaduct, Direction Macchietto, Direction Venezia, Notes and pk for each of them, which is the shape the original compiler chose rather than one imposed here.

26 entries fall below a kilometre, short enough that portals and approaches usually decided their cost more than the bore itself. Read down the direction macchietto column, the 36 values run from 25 to 3 485 with a midpoint at 394; the spread rather than the maximum is what says how uneven this set is.

Between the longest and the tenth-longest the drop is 2.39 km, which is the part of the table that changes when a single scheme opens. Where one of these 42 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.

This page records the structures catalogued along the A27 in Italy, in a tunnel almanac maintained at this address since the late 1990s. The captions name 25 distinct places and structures — Fadalto, Cadola and Tangenziale among them — and those names are the index into the length tables where each is recorded with its own figure.

Reading the figures

Lengths for Italy are recorded in metres which is how the operators publish them and why the shortest entry here reads as 25 m and not a rounded figure. The longest entry is 151.6 times the shortest and 10.1 times the median, which is the quickest measure of how uneven the table is.

A new scheme in Italy would have to beat 3.79 km to change the head of this table, and that is the figure worth rechecking when one opens. The note column records 12 exits, 4 motorway connections, 3 toll barriers and 2 service areas along the route, in running order rather than by size.

The eighth longest is Sarni Oil at 0.7 km, which is about where this record stops being about record holders and starts being about ordinary infrastructure. The ten longest average 2.69 km against 0.41 km for everything below them, and that ratio is the clearest thing this table says about the distribution.

Laid end to end the entries on this page would run 40.19 km, which is a number with no engineering meaning but a useful sense of the scale of what is catalogued. De-icing is a portal problem rather than a tunnel one: the bore stays above freezing long after the approach road does not.

The material on this page is held in 8 captions rather than in running text, 71 words of it, each written against the image or row it belongs to by the compiler who put the page together. The kilometre point is recorded for each structure on the A27, which is how the operator identifies it.