Our verdict
Come at dusk in winter for the starling murmuration, one of Britain's great wildlife spectacles, on a flat, pram-friendly path. The car park fills fast.
A premier wetland of reedbed, open water and willow carr reclaimed from old peat workings. Bitterns boom in spring; in winter, vast clouds of starlings wheel overhead before roosting.
RSPB reserve on the Avalon Marshes. Flat trails and hides; keep dogs on leads for the birds.