Castle Acre is a village and civil parish in the English county of Norfolk. The village is situated on the River Nar some 4 miles (6.4 km) north of the town of Swaffham. It is 15 miles (24 km) east of the town of King's Lynn, 33 miles (53 km) west of the city of Norwich, and 103 miles (166 km) from London.
The village is best known today for the twin ruins of Castle Acre Castle and Castle Acre Priory, which lie immediately to the east and west of the village respectively. Both were founded soon after the Norman Conquest by William de Warenne, the first Earl of Surrey. At its heyday, Castle Acre played an important role in the affairs of the State, with many visits from royalty. Castle Acre itself was once a fortified town and still possesses one of its gates, the Bailey Gate. When first established, Castle Acre was one of the finest examples of Norman town planning in the country, and much of this can still be seen.
The civil parish has an area of 13.18 km2 (5.09 sq mi) and in the 2001 UK census had a population of 799 in 370 households, the population increasing to 848 at the 2011 UK census. The parish shares boundaries with the adjacent parishes of Rougham, Great Massingham, West Acre, South Acre, Newton-by-Castle Acre and West Lexham. The parish falls within the District of King's Lynn and West Norfolk.
The village lies some 0.5 miles (0.80 km) west of the A1065 Mildenhall to Fakenham road, but is clearly visible from the road. The hamlet of Fiddler's Green lies to the northeast of the village and is redirected here.