Twizell Castle (also spelt Twizel) is a Grade II* listed building and a Scheduled Ancient Monument which stands on a bend of the River Till at Tillmouth Park, Northumberland, northern England. Below it, the medieval Twizell bridge spans the river. It is located south-west of Berwick Upon Tweed. The site is visible from a public footpath, which passes the castle from the road. The gardens of the castle contain the earthwork remains of the once lost medieval village of Twizell, whilst the massive ruin presents the remains of an 18th-century castle which was never completed.