Wicken Fen is one of the best places near Ely to understand what the Fens looked and sounded like before drainage turned so much wetland into farmland. Boardwalks and trails cross reed beds, sedge fields, pools, and grazing land, with dragonflies in summer and strong birdlife year-round.
It is a National Trust reserve rather than a manicured park, so the pleasure is slow: watching water, wind, and wildlife in a flat landscape that changes with the light. Bring binoculars if you have them, and leave time for the visitor centre to make sense of the restoration work.