An experimental tube tunnel dug in the 1970s, then sealed up and never seen again, until recently. A recent structural inspection has taken photos of this little known part of London Underground's history.
After a couple of years of work, the Post Office Railway will start to take its first passenger trips through the tunnels under London next month.
There's an experiment taking place that might see old underground ticket offices turned into new potted gardens.
A short walk from Big Ben is a large exhibition about the tunnels under London, and -- much more importantly -- a working tunnel boring machine, made from Lego.
Look out, as a second TV series about the construction of the Elizabeth line (nee Crossrail) starts on BBC 2 next week.
Deep under the streets of Bristol lies an abandoned underground railway that served a secret purpose in WW2 and is only now starting to occasionally open its doors to curious visitors.
The long abandoned Post Office Railway is to start tours from July, with tickets going on sale next month.
Buried underneath part of the Regent's Park lies one of London rail heritage's stranger stories, an entire railway terminus that once rivaled Euston station, but now is empty, abandoned, and largely forgotten.
Earlier today, a major upgrade to Victoria tube station was completed, when an entire new entrance and set of escalators was opened to the public.
Around the middle of next year, it will be possible to take a ride through the disused tunnels of the Post Office Railway.