Every year, volunteers brave the icy Tuel Lane lock in West Yorkshire to clear leaves, litter – and pickled onions

It is said that an imitation Rolex watch was once found during the spring clean of the UK’s deepest canal lock. Today the most glamorous discoveries are a Tesco shopping trolley and an empty can of Sprite – but spirits are still high.

“I did once come across a full jar of pickled onions,” said Maureen Readle, a volunteer. “But that was a bit further up. Here it is mostly leaves.”