Owston Ferry Castle was in the village of Owston Ferry, some 12 kilometres (7 mi) to the north of Gainsborough

Gainsborough, Lincolnshire

Gainsborough is a town 15 miles north-west of Lincoln on the River Trent within the West Lindsey district of Lincolnshire, England. At one time it served as an important port with trade downstream to Hull, and was the most inland in England, being more than 55 miles from the North...

, Lincolnshire

Lincolnshire

Lincolnshire is a county in the east of England. It borders Norfolk to the south east, Cambridgeshire to the south, Rutland to the south west, Leicestershire and Nottinghamshire to the west, South Yorkshire to the north west, and the East Riding of Yorkshire to the north. It also borders...

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It is thought that the original castle on this site was erected soon after the Norman Conquest but that it was dismantled in 1095. It was rebuilt in 1173 by Robert de Mowbray to support Prince Henry

Henry the Young King

Henry, known as the Young King was the second of five sons of King Henry II of England and Eleanor of Aquitaine but the first to survive infancy. He was officially King of England; Duke of Normandy, Count of Anjou and Maine.-Early life:Little is known of the young prince Henry before the events...

 in the conflict with his father Henry II

Henry II of England

Henry II ruled as King of England , Count of Anjou, Count of Maine, Duke of Normandy, Duke of Aquitaine, Duke of Gascony, Count of Nantes, Lord of Ireland and, at various times, controlled parts of Wales, Scotland and western France. Henry, the great-grandson of William the Conqueror, was the...

 who subsequently had the castle destroyed.

The site of the motte remains as a broad grassy mound. The surrounding area is now a nature reserve

Nature reserve

A nature reserve is a protected area of importance for wildlife, flora, fauna or features of geological or other special interest, which is reserved and managed for conservation and to provide special opportunities for study or research...

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