The tunnel is 370 metres long and 15 metres under the Thames.
You can see behind me that the tunnel is a bit narrower at one point. This is because they had to strenghthen it after a bomb was dropped here in the Second World War.
I use the tunnel to get from the Isle of Dogs to Greenwich Park, where I chase my ball around. But you might use it to go Greenwich Market, or the National Maritime Museum or even to walk a bit further and go to Blackheath.
The tunnel is also part of the UK's National Cycle Route 1, if you ever want to ride your bike from Dover to Inverness...
See you next week