Castle, built 1490, demolished in 1645. The remains of the castle consist of a tower about 7.5m square standing to a height of 8m standing on a knoll, which has contemporary cultivation terraces on its south east flank. The monument is of unusual form with elements of both tower keep and quadrangular castle. The castle also incorporates the remains of the preceeding manor house. The castle was besieged by parliamentarian forces during the civil war and taken in 1645. (PastScape)
The ruins of the castle stand on a slight eminence half a mile or more to the east of Garstang, and consist of the remains of a single tower 24 ft. square externally, constructed of rubble sandstone masonry, with angle quoins, the walls of which are 5 ft. thick. Whitaker, writing about 1822, states that the building had been a. rectangle nearly approaching a square, with a tower at each angle standing diagonally to each adjoining wall. The interval between the two towers was 14 yds. on one side and 16 yds. on the other.' The elevation on which the castle stands is said to have been originally surrounded by a marshy swamp, the only natural connexion with firm land being on the north-east side, but the wet land has long been drained. It would, however, add to the defensive position of the building, and was probably a contributing factor to the choice of site, helping, in addition, to supply the moat, traces of which are still visible. Apparently nothing has been done to preserve the castle since the siege of 1645, the action of time and weather, supplemented by the local practice of using the ruins as a stone quarry, having reduced it to its present condition. The portion still standing is one of the western towers, the highest part of the walling of which, on the north-east and north-west sides, is about 25 ft. to 30 ft. in height. It shows internally marks of a wooden floor 10 ft. above the ground, and there was probably another floor above this; but the upper part of the walls is entirely gone and the building is open on the south side, the walls being only about 5 ft. above the ground. In the east angle is a passage-way 3 ft. 6 in. wide, which formerly led to the main building, and opposite in the west wall are three embrasures, one in the centre and one set diagonally at each angle, that on the west facing directly towards Garstang and commanding the bridge or ford across the Wyre. The interior of the tower, which measures 14 ft. 6 in. by 14 ft., is now strewn over with broken masonry, large portions of walling having fallen within the last forty years, and the lower parts of the external angles and masonry bordering the window openings are broken away. On the north-east side are garderobes, and in the portion of the south-west wall which still remains part of an embrasure like that on the north-west. The top of the knoll occupied by the ruins forms a square of about 35 yds., the excavation of which would probably disclose the foundations of the castle. (VCH)
Greenhalgh Castle is a late medieval castle which is an unusual variant of a tower keep castle. Both the form of the main keep, with its corner towers, and the absence of a defended outer enclosure are unusual. The form probably owes much to other types of castles and defended houses developing in the north at this date; these include the tower houses commonly found in the borderlands with Scotland, and quadrangular castles in which an open enclosure is surrounded by a defensive wall which has large corner towers providing domestic and other accommodation. Despite part destruction of the castle during the Civil War and some later stone robbing, Greenhalgh Castle survives reasonably well and is unencumbered by modern development. It retains upstanding medieval fabric and will also contain buried remains of the 15th century castle and the earlier medieval manor house which is known from documentary sources to have existed here. It will contribute to the study of the development of the castle in the north of England.
The monument includes the upstanding and buried remains of Greenhalgh Castle, an area of cultivation terraces immediately to the south east of the castle, and the site and buried remains of Greenhalgh manor house which preceded the castle. It is located on the top of a low knoll originally surrounded by a marshy swamp sometimes erroneously described as a moat. The summit of the knoll has been scarped to give a virtually square, flat top with steep slopes all round. The upstanding remains include the south west tower of what was originally a square keep with towers at each corner. The surviving tower is constructed of coursed sandstone facing stones with a rubble core and angle quoins. It measures approximately 7.5m square, stands up to a maximum height of 10m, and has walls an average of 1.6m thick. There are traces of the original entrance at the east corner. Arrow slits with splayed openings can be seen in the west and north corners and midway along the north west side. Traces of others are visible in the south west and south east sides and in the south corner. In the north east side there is a fireplace and at first floor level there are remains of windows. There are no upstanding remains of the three other corner towers, however, on all sides of the knoll's summit apart from the south west there are traces of a rubble bank up to 4m wide and 0.8m high which is interpreted as the foundation wall of the main block. On the south east slope of the knoll there are a number of well preserved agricultural terraces associated with the castle.
In the 14th and 15th centuries the manor, or estate, which had its headquarters at Greenhalgh, belonged to the Lord of Wyresdale, but it was given to Thomas Stanley, first Earl of Derby, as a thank-offering by Henry VII for his support at the battles of Bosworth (1485) and Stoke (1487). In 1490 the earl received permission to fortify his manor house by constructing the castle, a square tower with additional towers at each corner. The monument is of unusual form with elements of both tower keep and quadrangular castle, and as such it may owe much to the quadrangular castle building tradition which was common during the 15th century. It is unlikely the Earls of Derby resided at the castle, indeed custody of the castle was given to Thurstan Tyldesley and then Sir Richard Shireburne during the mid-16th century. During the Civil War the castle was held for the king by men loyal to the Earl of Derby, but was not besieged until 1645 when the garrison surrendered. Thereafter the timber was removed, the walls breached, and the castle rendered untenable. (Scheduling Report)