House incorporating fragments of a medieval tower house. Licence to crenellate 1340; colliery agent's house added c.1832 (possibly by John Dobson); enlarged and largely rebuilt in Tudor style 1877-80 for William Lisle Blenkinsopp Coulson. First floor of 1880 entrance block removed in 1986. Dressed and squared stone incorporating some Roman material; roofs and chimneys of occupied west and north ranges are not visible; entrance block and agent's house now roofless ruins. Square-plan entrance block with agent's house set back on east and L-plan north range and house, with wall enclosing small yard, on west. Tudor style c.1880 details. Mainly 2- and 3-light mullioned windows under hoodmoulds.
2-bay entrance block incorporates medieval fabric especially in east will: 4-centred moulded doorway (in square frame with foliage-carved spandrels under hoodmould) and 3-light window on front. 2-bay agent's house has window with re-set cable-moulded surround on front and projecting bay window on east return. 2-storey occupied house at west has one-bay front and 2-bay returns: 2-light first-floor-oriel window on front; embattled parapets; medieval fabric (including ground-floor room with rubble ceiling and external wall footings) at north-west corner. Wall enclosing yard has central round archway and incorporates re-set carved Roman and medieval fragments. 2-storey, 6-bay north range with 2-bay rear elevation of agent's house at east: 2- and 3-light windows and embattled parapet on 6-bay section; 3-light windows with arched heads on agent's house. Archway and former stable block (now restaurant) on west return of occupied house are not of special interest. Apart from the occupied house and north range, the remains are in a derelict condition. (Listed Building Report)
The earliest mention of the castle is found in a licence to crenellate issued by Edward III on 6th May 1340, to Thomas de Blenkensop; the 1415 list appends the marginal note 'fortalicum' to the entry 'Castrum de Blekensope', whilst the 1541 survey states the tower as in decay. By the 16th century the Blenkinsops were resident at Bellister Castle (NY 76 SW 5), and by the 17th century Dryburnhaugh (later renamed Blenkinsopp Hall) (NY 66 SE 4) was also a family residence.
Blenkinsopp Castle continued in poor repair and by 1801 some sort of poor house had been built into the ruins; the Blenkinsopp Coulsons developed adjacent collieries, and in 1832 or 1833 their colliery agent had a new house 'in the castellated style' built onto the east side of the ruins, perhaps by John Dobson.
William Lisle Blenkinsop Coulson virtually rebuilt the castle in 1877-1880 as a Victorian mansion; due to financial problems it was soon sold to the Joiceys, with whom it remained for around 70 years; in the latter part of this period it was converted into a hotel, which was gutted by fire in 1954. Parts of the ruins were demolished as dangerous in the 1960s, and a further section of Victorian fabric was taken down after 1986.
18th and 19th century antiquarian descriptions and illustrations, provide a valuable source when it comes to reconstructing the form of the medieval castle. Hutchinson wrote c.1780 'this castle consisted of a square tower, built on an artificial mount surrounded by an outward wall at a distance of only four paces, of equal height with the interior of the building'; he adds that 'the out wall towards the west has been removed of late years, and lays the tower open on that side; three vaults support the building, one of which is 18 feet wide'.
Of the various illustrations to survive, one of the most telling is a photograph of c.1870, taken from the south east (original in Blenkinsopp Hall); this shows the tower with a 16th century window of three round-headed lights in its south wall, and a parapet stepped out on four oversailing moulded courses. Above the ruined walls rose an extraordinary slender tower with a strange combination of Gothic and Classical details, which must have been a chimney or ventilation shaft for a colliery within the walls.
Blenkinsopp Castle as remodelled 1877-1880 consisted of an almost square two storeyed block (containing the entrance hall) with a small courtyard on the west enclosed by lower service ranges on north and west; to the north east of the main block, and overlapping its east wall, was a second almost square block - the early 19th century agent's house.
The bulk of the fabric was coursed rubble with ashlar dressings, larger squared stone (with reused Roman material; several carved and inscribed stones were found during the remodelling) appeared in the south and east walls of the main block, and in the external walls at the north west corner of the service court. Most of the architectural features were in a Tudor style.
Only the west service range and the adjacent section of the north range today remain roofed and in use. The remainder of the building is a decaying and rather overgrown ruin. The principal medieval survival is the east wall of the main block, which is still 1.4m thick, although obviously cut back internally; this is the east wall of the original tower, which from old map evidence seems to have measured c.14m north-south by c.15m east-west. The only old feature visible in the wall is part of a circular arch visible internally; this might have been the original entrance to the tower. Medieval walling - up to 2m thick - also remains in the external walls of the service court ranges. This would appear to represent the north west corner of the outer wall. In recent years footings of thick north-south walls have been seen in the service court (presumably the west side of the main tower) and to the south of the mine agent's house (part of the eastern outer wall).
Reset in the south wall of the agent's house is a 16th or early 17th century square headed window with a cable moulded surround (compare Sundial House, Harnham (NZ 08 SE 59)).
The original form of the castle - a massive tower, with vaulted basements closely hugged by a lofty curtain wall - is not easy to parallel, although Pendragon Castle (Westmorland) had a plan something like this. Blenkinsopp would appear to have been a small but sophisticated castle rather than a simple tower house; it may well have been a 14th century building, associated with the original licence to crenellate.
While relatively little medieval fabric now survives above ground, there may still be considerable sub-surface remains to the south and south east of the ruins; the position of the outer south wall and possibly a gatehouse must lie beneath what is now a car park. (Northumberland HER ref. Ryder 1994-5)