Tunnels and Viaducts on the A52 Motorway in Italy, by Kilometre Point

• 10entries listed
• 1.58 kmlongest bore
• 3.85 kmtotal length

The record table

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

How this table is compiled

The next two longest are Cerchiarello at 0.85 km and San Rocco at 0.5 km. The table on this page runs to 16 rows and records Tunnel / Viaduct, Direction Rho, Direction Sesto S.Giovanni and Notes for each of them, which is the shape the original compiler chose rather than one imposed here.

9 entries fall below a kilometre, short enough that portals and approaches usually decided their cost more than the bore itself. Read down the direction rho column, the 10 values run from 45 to 1 583 with a midpoint at 175; the spread rather than the maximum is what says how uneven this set is.

The route table lists 10 structures with a recorded length, giving both carriageways where the two bores differ. The material on this page is held in 12 captions rather than in running text, 105 words of it, each written against the image or row it belongs to by the compiler who put the page together.

This page records the structures catalogued along the A52 in Italy, in a tunnel almanac maintained at this address since the late 1990s. The captions name 29 distinct places and structures — Milano, Fiera and Sesto among them — and those names are the index into the length tables where each is recorded with its own figure.

The three longest entries alone account for 2.93 km of the 3.85 km on this page, which is 76 per cent of the total from 3 of 10 rows. 5 entries sit above the median and 5 at or below it, so the table is evenly weighted and not clustered at one end.

Reading the figures

Between the longest and the tenth-longest the drop is 1.54 km, which is the part of the table that changes when a single scheme opens. Where one of these 10 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 45 m and not a rounded figure. The longest entry is 35.2 times the shortest and 9.0 times the median, which is the quickest measure of how uneven the table is.

A new scheme in Italy would have to beat 1.58 km to change the head of this table, and that is the figure worth rechecking when one opens. The eighth longest is SP9 at 0.11 km, which is about where this record stops being about record holders and starts being about ordinary infrastructure.

On 1 of the structures here the two carriageways are not the same length, which is why the archive records each direction separately rather than one figure per crossing. The note column records 24 exits, 7 motorway connections, 1 toll barriers and 1 service areas along the route, in running order rather than by size.

The tunnel / viaduct column names 10 distinct entries on this page, San Rocco and Viganò De Vizzi among them, each traceable to the operator or administration record it was taken from. Span rather than total length is what places a bridge in a record, because the span is the engineering and the approaches are not.