The Science Museum’s Artist-in-Residence, Conrad Shawcross, has created a beguiling piece of art work called Chord. More beguiling still is the location, deep inside the bowels of Holborn.

I’ve always wanted to get into the Kingsway tram tunnel. I used to pass it every day when I first came to London. It might just have been my first glimpse of ‘secret’ London – those bewitching tunnels and spaces normally off limits to the public, which I’ve since made something of a hobby out of exploring.

The Kingsway tunnel is an old tram underpass, closed to the public in 1952. It’s since been used for council storage, film shoots and, bizarrely for a space below sea level, a flood-defence control centre.

The passage still contains tram rails, remains of subterranean stations and the occasional period Tube map. It also basks in a thick cloud of dust, and an aural pit-pat of dripping water. You can immediately see why this is a popular film set.

The artwork sits a few hundred metres into the tunnel, and is also impressive. Two diametrically opposed rotors slowly turn, weaving together different coloured threads along the tunnel length.

Very, very ponderously, the two rotors move apart. So, over the month of the exhibition, the chord will get gradually longer.

I won’t write too much more because (a) others have, (b) it’s better experienced in person, and © I have a short video.

Kingsway tram tunnel ‘Chord’ artwork from Londonist on Vimeo.

Awesome stuff. It’s only tenuously relevant to a scientific audience but, hey, this is my blog and I’ll write about what I like.

The experience is free, but you have to pre-book. Tickets are shifting quickly and there are only a few dates left, so snap ’em up now.