Harrold gathers around a triangular green on the Great Ouse, with two oddities on it: an eighteenth-century octagonal market house on Doric posts, and a small round stone lock-up built in 1824 to hold prisoners bound for Bedford. A long medieval bridge and causeway cross the river. Next door is Harrold-Odell Country Park, with lakes and meadows for easy walking; Odell sits on the far side.