Unless you know the area, you might not realise that there’s a long deep tunnel running under Islington and that a couple of times each month, the public can take a tour of it. This is the Islington Tunnel, and it links the eastern and western halves of the Regent’s Canal and owes its existence to the problem of how to get the canal past the hill that Islington sits on.
A bit of history
Just over 200 years ago, when the Regent’s Canal was built around the edges of London as it was back then, they hit a problem — the hill at Islington. They had three choices – to go around it by a long route, go over the hill, or go under — and they went under.
The reason for the tunnel is simple, although a series of locks over the hill is a lot cheaper to build, they’re slow to use and expensive to operate, whereas a tunnel is expensive to build, but, occasional maintenance aside, quick to use and free to operate.
To build the tunnel, a series of shafts were dug down along the route so that the tunnel could be dug at the same time all the way along the route, and while work was steady, they encountered problems with the ground conditions requiring far thicker brickwork inside the tunnel to stop it collapsing.
In the end it cost £40,000 to dig the tunnel, far higher than the original estimate. Considering that the entire Regent’s Canal was expected to cost £400,000, the tunnel represented a tenth of the total cost of the canal between Paddington and Limehouse. Although completed at the end of 1818, about three years after work started, the tunnel remained closed until 1820, when the rest of the Regent’s Canal was completed.
In those days, canal boats were hauled by horses, working in relay teams all along the canal, but when they got to the tunnel, it wasn’t wide enough to include a towpath for the horses.
So in those days, each canal barge was pushed through by “legging”, and that is men lying on their backs would push the barge along with their legs on the tunnel wall. Fortunately, that was replaced in just a few years with a steam engine pulling a steel cable in a loop, and barges just hooked onto the cable to be dragged through.
Now barges are expected to make their own way down the tunnel.
Until the 1970s, when the canals were still industrial, it was pretty much impossible for the general public to see inside, but now that the canals are more decoratively for leisure, there are regular boat tours through this hidden world underneath the heart of Islington.
Take a trip through the canal tunnel
Run by the Canal Museum near King’s Cross, the tour is simple, but wonderfully atmospheric — a trip from the museum in a barge through the tunnel to the other end, and back again. I had planned to do this in 2020, on the 200th anniversary of the canal opening, but, we all know what happened to plans in 2020.
Arriving at the museum, you may worry that the barge seems to be indoor seating with a bit of outdoor space at the front, and once inside the barge, with the small windows hard to see out of you might worry a bit. But, as the barge pulls out from the museum and the volunteer explains the history, you’re invited to sit outside. Hurrah!
The tours are for small groups, and there’s just about enough space for everyone to sit on the outside, and that’s where you want to be, for the views of the long tunnel and the 200+ year old brickwork.
The chugging sound of the barge dominates as we glide into the tunnel mouth and the bright sunshine is replaced with the reddish brown light reflecting off the bricks that line the tunnel. The barge has a floodlight to show off the tunnel, and you can easily see the exit in the distance, so it’s not, as some might worry, scary to be in a dark tunnel.
Mostly dry all the way along, there’s one area of ceiling that leaks from the ground above, and dropped a big cold clammy drip on my head, and I am just pleased it missed the back of the neck otherwise I might have jumped out of the boat in shock.
The tour guide points out the industrial history at the far end of the tunnel where the boat turns around and repeats the journey.
Although we’re sat here chugging along, with a few areas pointed out, it’s an odd mix of exciting and yet also delightfully relaxing to glide through this stygian space. The tour takes between 45-60 minutes as the tunnel is one-way traffic only and sometimes there’s a delay to get inside so allow for the full duration if making a visit.
The tunnel boat trips cost £12 for adults, £11 for concessions and £8 for children — and that includes admission to the museum as well – which is usually £3-£6, so for an adult, the canal tunnel is just £6 on top of the museum entry.
That’s a bargain.
At the time of writing, tours are available on the following afternoons.
- Thu 4th Aug 2022
- Sun 14th Aug 2022
- Thu 18th Aug 2022
- Fri 2nd Sep 2022
- Sun 11th Sep 2022
- Fri 16th Sep 2022
- Sun 25th Sep 2022
- Sun 9th Oct 2022
- Sun 23rd Oct 2022
The tours need to be booked in advance from here.
The leak from above is where the canal is below Duncan Terrace Gardens. This is where the New River’s aqueduct used to run, supplying drinking water to New River Head’s basins and to the rest of London.
The water, which runs in year-round, is from that aqueduct, probably not all the way from the Lea at Great Amwell, but accumulated in the buried base of the old aqueduct.
Nice piece, and glad you enjoyed the trip through the Islington tunnel. I navigate canal tunnels up and down the country and the engineering and architecture is amazing. Our canal and railway heritage is world-class. I always put on a waterproof hat, because most tunnels drip plenty! I often hear the yells of people on other boats in a tunnel, who haven’t yet learned that important fact. In the longest tunnels it’s easy to lose your sense of “space” in the dark and find yourself scraping your paintwork along the tunnel wall.
I would recommend the Canal museum too, a London gem.
Lovely article, thanks for that. The tunnel trips are not in barges ( wide beam) they are in narrowboats ( narrow beam).
This tunnel is fascinating – well worth a look.
The Hidden Depths company also run several trips a day through it too, from March til October (although the museum is extra if you want to got here too!)