Qualla: Dublin Port Tunnel

Dublin Port Tunnel: Introduction

Sat, 23 May 2026 00:00:00 GMT

Photo credit D., CC BY-SA 4.0. By the late 1990s the morning rush hour in Dublin had become a specific kind of misery. The city's port -- one of the busiest in Europe -- sat at the eastern end of the Liffey, hard against the city centre. Thousands of articulated lorries a day ground through narrow Georgian streets in low gear, belching diesel past schoolchildren and pensioners on their way to the quays. The fix, when it came, was ambitious: two parallel tunnels, 4.5 kilometres long, bored 30 metres below the rooftops of north Dublin. The engineers gave the boring machines girls' names, in the old tunnelling tradition. Meghan ate through 650 metres of soft clay. Grainne chewed through 2,600 metres of hard Dublin limestone. The result, opened on 20 December 2006, is still the fourth-longest urban motorway tunnel in Europe.

Read more: Dublin Port Tunnel on Qualla

Image: D. | CC BY-SA 4.0

Dublin Port Tunnel: Meghan and Grainne

Sat, 23 May 2026 00:00:00 GMT

Photo credit Estoy AquÃ at en.wikipedia, CC BY 2.5. The two tunnel-boring machines were built by Herrenknecht of Germany and arrived at Dublin Port in 105 separate pieces aboard three ships. Reassembled, each was 156 metres long and 12 metres in diameter -- the size of a city block, on its side, with cutting teeth. The launch shaf...

Read more: Dublin Port Tunnel on Qualla

Image: Estoy AquÃ at en.wikipedia | CC BY 2.5

Dublin Port Tunnel: The Railway Above

Sat, 23 May 2026 00:00:00 GMT

Photo credit Lumijaguaari, CC BY-SA 3.0. The trickiest stretch was a sixty-metre section near Fairview where the new tunnel had to pass directly under the Dublin-Belfast railway. The railway sits on a Victorian-era embankment of soft fill resting on alluvial sand and silt, and trains run on it all day -- the InterCity s...

Read more: Dublin Port Tunnel on Qualla

Image: Lumijaguaari | CC BY-SA 3.0

Dublin Port Tunnel: Houses That Shook

Sat, 23 May 2026 00:00:00 GMT

Photo credit Public domain. Boring through hard limestone shakes the ground above it. In the Marino area -- a neighbourhood of small, careful semi-detached houses built in the 1920s -- residents felt their homes vibrate as Grainne ground past 23 metres below their kitchens. The contractor surveyed 241 prope...

Read more: Dublin Port Tunnel on Qualla

Image: Public domain

Dublin Port Tunnel: The Tolls and the Lorries

Sat, 23 May 2026 00:00:00 GMT

Photo credit Sarah777, Public domain. The Port Tunnel is tolled, but only for cars. Heavy goods vehicles (HGVs) pass for free, and from 7am to 7pm on weekdays a city-centre ban prevents any five-axle truck from entering the streets they used to dominate. The cumulative effect on Dublin's quays has been transformative...

Read more: Dublin Port Tunnel on Qualla

Image: Sarah777 | Public domain

Dublin Port Tunnel: Underground Run

Sat, 23 May 2026 00:00:00 GMT

Photo credit Donaldytong, CC BY-SA 3.0. Three times since opening, the tunnel has closed entirely for a curious purpose: people have run 10 kilometres through it. The Underground Run, held most recently on 26 March 2017, drew 2,400 runners and raised money for the homeless charity Focus Ireland. There is something cine...

Read more: Dublin Port Tunnel on Qualla

Image: Donaldytong | CC BY-SA 3.0