Wild in Walthamstow: Europe’s biggest urban wetlands opens

Few locals know about Walthamstow Wetlands in north London, which opens on Friday. But now they, and nature lovers everywhere, can enjoy this amazing bird reserve for free

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We're strolling along Songbird Walk, beneath a row of waterside poplars very like ones Monet painted in Normandy. The October sky is grey but the footpath is lined with colourful wildflowers: yellow gorse, purple knapweed, white campion. With a liquid twittering, a flock of goldfinches swoop overhead, then a clear, penetrating song bursts from the bushes to one side. "Ooh, a Cetti's warbler," says wetlands director Veronica Chrisp.