[Article] The forgotten street found behind a hidden library door

I like cool things like this

Meanwhile in London

Eva Green plays the Professor...

[I'm saying this sounds like the start of a really good BBC series]

For a "forgotten" street found behind a hidden library door, I didn't expected a well lid passage with tons of cabling rails and service pipes, which I don't know, sounds like the opposite of what the title implies.

Discovered in the 1990s. It’s been known/used for decades now.