Railway Tunnels in Canada — Complete List by Length

• 25entries listed
• 14.72 kmlongest bore
• 1860–1995openings span
• 67.26 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 12.95 km, which is the part of the table that changes when a single scheme opens. Where one of these 25 lengths disagrees with an operator's own figure for Canada, the table keeps the published value and notes the difference instead of averaging the two.

Lengths for Canada are recorded in metres which is how the operators publish them and why the shortest entry here reads as 509 m and not a rounded figure. The 25 rows for Canada are ordered by length, not by date, so the 1995 opening sits well down the table without being any less current.

A new scheme in Canada would have to beat 14.72 km to change the head of this table, and that is the figure worth rechecking when one opens. The longest entry is 28.9 times the shortest and 12.3 times the median, which is the quickest measure of how uneven the table is.

4 of the 25 measured entries exceed five kilometres, and those are the ones that carry a full ventilation and escape regime. Laid end to end the entries on this page would run 67.26 km, which is a number with no engineering meaning but a useful sense of the scale of what is catalogued.

Further down the table, Mount Royal is recorded at 4.97 km and Thornton at 3.42 km. The table on this page runs to 27 rows and records Tunnel, Length, Date of opening and Line, comment for each of them, which is the shape the original compiler chose rather than one imposed here.

Reading the figures

Dated entries run from 1860 to 1995, and the busiest decade is the 1910s with 5 recorded openings. Read down the length column, the 25 values run from 509 m to 14 723 m with a midpoint at 1 201 m; the spread rather than the maximum is what says how uneven this set is.

Roughly 0 of the dated entries opened in this century, which is a rough measure of how much of the network is recent. The captions name 24 distinct places and structures — Pass, Canada and National among them — and those names are the index into the length tables where each is recorded with its own figure.

The dated entries carry 14 distinct opening years across 135 years, and the median opening year is 1918. The material on this page is held in 13 captions rather than in running text, 122 words of it, each written against the image or row it belongs to by the compiler who put the page together.

The longest entry is Mount MacDonald, at 14.72 km, opened in 1988. 27 of the 27 rows carry an entry in the line, comment column — 100 per cent of the table — and that column is where the qualifications live: tube counts, closures, boundaries and the reason a figure reads the way it does.

Eighth on the list is New St. Clair at 1.87 km, which is where the table stops being about record holders and starts being about ordinary infrastructure. The dated entries fall across 14 different years, which is a rough measure of whether this was a sustained programme or a handful of separate schemes.