Tunnels and Viaducts on the A29 Motorway in Italy, by Kilometre Point

• 47entries listed
• 1.65 kmlongest bore
• 17.98 kmtotal length

The record table

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

How this table is compiled

The table below lists 47 entries with a recorded length, each giving a name, a length in metres and, where documented, the year of opening. The tunnel / viaduct column names 50 distinct entries on this page, Sferracavallo and Isola delle Femmine among them, each traceable to the operator or administration record it was taken from.

The three longest entries alone account for 4.57 km of the 17.98 km on this page, which is 25 per cent of the total from 3 of 47 rows. The shorter half of the table totals 3.44 km against 14.53 km for the longer half, from the same number of rows.

Between the longest and the tenth-longest the drop is 1.16 km, which is the part of the table that changes when a single scheme opens. Where one of these 47 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 65 m and not a rounded figure. The longest entry is 25.4 times the shortest and 5.9 times the median, which is the quickest measure of how uneven the table is.

Also recorded here are Canalotto at 0.72 km and Marchese at 0.64 km. A tunnel list for Italy reads differently from a neighbouring country's: 0 of these 47 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.

Reading the figures

A new scheme in Italy would have to beat 1.65 km to change the head of this table, and that is the figure worth rechecking when one opens. The eighth longest is Pozzillo at 0.53 km, which is about where this record stops being about record holders and starts being about ordinary infrastructure.

The route crosses 2 provinces, recorded in the note column by their vehicle-registration codes (PA, TP), which is how the operator identifies a section. Only 24 of the 72 rows carry anything in the km column, so that field describes a minority of this table and the rest of the rows are recorded without it.

The 72 entries are grouped on the page under 3 headings — exit alcamo ovest (38), exit tommaso natale (23) and prov. pa / prov. tp (11) — a classification the table carries as section breaks rather than as a column of its own. Italian motorway inventories list tunnels and viaducts together in running order along the A29.

Read down the length direction mazara column, the 49 values run from 35 m to 1 650 m with a midpoint at 280 m; the spread rather than the maximum is what says how uneven this set is. Tunnel building in Italy is shaped by geology and settlement pattern as much as by transport policy.

Read down the length direction palermo column, the 50 values run from 35 m to 1 650 m with a midpoint at 265 m; the spread rather than the maximum is what says how uneven this set is. Wartime damage closed several crossings for years, and a few were never reopened to their original use.