Tunnels and Viaducts on the A35 Motorway in Italy, by Kilometre Point

• 12entries listed
• 1.26 kmlongest bore
• 3.89 kmtotal length

The record table

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

How this table is compiled

Between the longest and the tenth-longest the drop is 1.23 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 21 m and not a rounded figure. The longest entry is 60.0 times the shortest and 11.5 times the median, which is the quickest measure of how uneven the table is.

11 entries fall below a kilometre, short enough that portals and approaches usually decided their cost more than the bore itself. Read down the direction brescia column, the 13 values run from 19 to 1 260 with a midpoint at 110; the spread rather than the maximum is what says how uneven this set is.

The eighth longest is Canale Muzza at 0.08 km, which is about where this record stops being about record holders and starts being about ordinary infrastructure. The ten longest average 0.38 km against 0.03 km for everything below them, and that ratio is the clearest thing this table says about the distribution.

The twelfth longest, Naviglio Cremona at 0.02 km, sits close enough to its neighbours that which of them ranks higher depends on how each was measured. 9 of them are under 500 metres, which on a route of this kind usually means a cut-and-cover section or a short spur and not a driven bore.

Reading the figures

This page records the structures catalogued along the A35 in Italy, in a tunnel almanac maintained at this address since the late 1990s. Laid end to end the entries on this page would run 3.89 km, which is a number with no engineering meaning but a useful sense of the scale of what is catalogued.

The route table lists 12 structures with a recorded length, giving both carriageways where the two bores differ. Fiume Serio at 0.93 km and Fiume Oglio at 0.69 km follow it, and lengths are given per carriageway because the two bores of a dual route are rarely cut to the same length.

The entries sum to roughly 3.89 km of bore, an average of about 0.32 km each, though that average describes no actual row. A fault zone crossed at an angle is longer to pass through than the same fault crossed square, which is why alignments bend for reasons the map does not show.

The next two longest are Fiume Serio at 0.93 km and Fiume Oglio at 0.69 km. The table on this page runs to 18 rows and records Tunnel / Viaduct, Direction Brescia, Direction Milano and Notes for each of them, which is the shape the original compiler chose rather than one imposed here.

Also recorded here are SS.Fermo e Rustico at 0.12 km and S.P.62 at 0.11 km. Read down the direction milano column, the 13 values run from 19 to 1 260 with a midpoint at 98; the spread rather than the maximum is what says how uneven this set is.