The Tube sign drawn by Ann Singh
© Ann Singh, Newbridge School Ilford, Essex

2. The shortest distance between two stations is the 0.16 miles between Leicester Square and Covent Garden.

3. Pigeons are regularly observed getting onto trains in north and west London to travel into the centre for food. At nightfall, they use the trains to return to their roosts in the suburbs!

4. There are 409 escalators, which do the equivalent of two round-the-world trips a week.

5. Only 29 of the 287 stations are south of the Thames.

6. Eight Tube stations are said to be haunted - apparently there's a ghost of a Black Nun at Bank. Find out more about the ghostly goings-on here

7. Every day, around 30 million litres of water from underground streams leaks into the Underground. It is constantly removed by 1,030 pumps.

8. Only one baby is known to have been born on the Tube - a girl born in 1924 on a Bakerloo Line train at Elephant and Castle. Her parents christened her Thelma Ursula Beatrice Eleanor - read her initials!

9. There are around 40 abandoned stations on the Underground. Read about the disused stations here

10. The deepest point is on the Northern Line in Hampstead, where trains run 220m below ground.