It's been under water for almost two centuries, but today visitors to one of north London's locks got a rare chance - to take a tour inside.
Camden Lock has been drained for restoration work, exposing the structure of the chamber.
It'll cost 130 thousand pounds to replace both sets of gates and repair the timber work.
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A 24-year-old man has been arrested on suspicion of murder after the body washed up on the Thames shoreline.
Seven people have now been arrested after a man died from serious head injuries
The 38-year-old officer was on his way home from a night shift when he collapsed. His death is not being treated as suspicious.