You might have wondered whether the hidden rivers of London matter all that much, because they’re… well… hidden!

Not any more: intrepid cameraman Farokh Khorooshi has filmed the River Fleet at one of the few points it can still be seen flowing in Hampstead.

Nowhere in Hampstead is very far from the Fleet or one of the other subterranean rivers that flow into the Thames. So we say, take a look… remember the considerable pressure that can result from a flow of water… and have another think about that basement you’ve been planning.