Wicken Fen, the National Trust's first nature reserve, began with two hectares bought in 1899 and is now one of Europe's most important wetlands, the first UK reserve to record 10,000 species. The core is Sedge Fen, a remnant of undrained fenland crossed by a raised boardwalk with two level-access hides, while the Lodes Way leads out to Adventurers' Fen, where Konik ponies and Highland cattle graze wet grassland and reedbeds under the 100-year Wicken Fen Vision. Look for the Fens' last working wooden windpump, the 1930s Fen Cottage and the Docky Hut Cafe. Dogs under close control are welcome on the wider reserve, but only assistance dogs go on Sedge Fen. Reviewers mention marsh harriers and the hides, so bring binoculars. Tips from regulars: parking is pay and display, with members scanning their card for a free ticket, and out of season only the boardwalk and woodland walk are open, to protect the peat.