Underground London - Islington tunnel Regent's Canal

 Not really underground, but I am including it as it is a long tunnel that can only be accessed by boat. The tunnel is on Regent's Canal in London, and runs under Islington town centre. Boat trips are run by the Canal Museum near King's Cross station. The museum has an underground ice well which I visited in 2019.

Tickets for the boat tour include entry to the museum, as the boats leave from the dock outside the museum, in Battlebridge Basin. I chose the last tour of the day, which was a one way through the tunnel and ended near Angel station. All the other tours do a return trip through the tunnel and back to the museum. 

Apparently on some boats you can sit outside, but on my tour there was only inside seating, with limited open windows, so it wasn't so good for photos. 

After a safety briefing the boat chugs out to the canal and soon approaches the tunnel. We had to tie up and wait for a boat to come through, as there is only enough width for one boat in the narrow tunnel. The west portal of the 875 m long tunnel -

I took this photo in August 2020 -

The tunnel opened in 1820. In those days the canal boats were pulled along by horses. As there is no towpath inside the tunnel, the horses were taken up and over the tunnel, leaving the boat men to leg through the tunnel -

Unfortunately I didn't manage to get any photos inside the tunnel as it was dark and there wasn't much to take apart from the walls, but this photo on IanVisits has a decent shot. I just managed to take a photo through the front as we were leaving the tunnel -

Looking back at the east entrance -

and this info board is from Nov 2020 -

Another boat following ours -

After the tunnel we went under the Danebury St bridge then came to the City Road lock. As we were only doing the tunnel one way, we went through the lock and back again. Before going through, we had to tie up to wait for the lock to fill. The red narrow boat "Angel II of Islington" is used by a charity.

The first lock gate has opened and we can go through and wait inside the lock for the next gate to open.

Water level is going down -

When the water has drained out, we can go through -

We went into City Road Basin where we turned round

Map of Regent's Canal

Read more on Islington tunnel on the Canal Museum page, also on Wikipedia.