Bishops Gate, 42 Mussenden Road, Downhill, Castlerock, Co. Londonderry, BT51 4RP

Bishops Gate

Bishops Gate is a Grade A listed structure comprising a free-standing triumphal stone arch with an attached two-bay single-storey stone gate lodge, built around 1785 to the designs of Michael Shanahan. The buildings serve as the easternmost entrance to the Downhill Estate and are situated on the north side of Mussenden Road, accessed via a short slip road at a lower level than the road itself.

The Triumphal Arch

The triumphal arch faces south and is built in sandstone ashlar. The central feature is a round-headed arch with a fluted archivolt rising from dentiled and fluted impost mouldings. These mouldings are supported on a pair of flat-panelled squat pilasters bearing paterae carved into the plain spandrels. The arch is flanked by a pair of engaged Doric columns with fluted necks. These columns support an architrave and frieze embellished with bucrania and bishop's mitre carvings, with a plain framed tablet at the centre. The arch is surmounted by a full pediment with mutules, and a carved coat of arms is set within the tympanum.

Flanking the pedimented arch are lower screen walls built in channel-rusticated sandstone ashlar. Each screen wall terminates at its inner end with a responding flat-panelled squat pilaster supporting a dentiled and fluted frieze embellished with paterae. The screen walls are surmounted by raised parapets decorated with bell-flower garlands, paterae, and guilloche trim. The western screen wall contains a blind niche, while the eastern screen wall features an arched pedestrian entrance. The north elevation of the pedimented arch mirrors the south elevation in its detailing, with a fluted frieze and a further coat of arms in the tympanum. The flanking screen walls on the north side are built in coursed rubble basalt with a voussoired arch to the pedestrian entrance.

The arch is fitted with a pair of replacement wrought-iron gates. The pedestrian entrance is fitted with an arched double-leaf timber door with raised-and-fielded panels.

The Gate Lodge

The gate lodge is rectangular on plan and set at a right angle to the triumphal arch, with the eastern screen wall abutting the centre of the front western elevation. The roof is hipped with natural slate and rolled lead ridges. A central sandstone ashlar chimneystack with vermiculated quoins and a single octagonal clay pot rises through the roof. The roof sits behind a lead-lined sandstone ashlar parapet wall with a cavetto moulded cornice below. Cast-iron guttering is supported on drive-through brackets with timber fascia to the north and east elevations, and cast-iron downpipes drain the roof.

The western and southern elevations are built in sandstone ashlar with a plain plinth course. The northern and eastern elevations are constructed in uncoursed rubble basalt. Each corner of the lodge is finished with a cluster of colonettes rising to the cornice and surmounted by sandstone pinnacles on diminutive pedestals.

The principal western elevation is four windows wide, with two blind windows towards the north end and three openings towards the south end. Round-headed window openings feature vermiculated voussoirs and quoined surrounds with flush vermiculated sills. All windows are replacement multi-pane timber sash windows with ogee horns. A pointed-headed door opening is set between the southern windows. The door opening is flanked by clustered colonettes on plinth blocks with a matching arched surround and a replacement hardwood panelled door. The door opens onto a stone platform with five stone steps.

The northern side elevation contains a single round-headed window opening with a voussoired basalt head and a replacement timber casement window.

The rear elevation is abutted at its south end by a single-bay single-storey over basement rendered extension, built around 1970. This extension has a hipped natural slate roof and timber casement windows with concrete sills.

The southern side elevation is two windows wide, detailed to match the front elevation. A rendered wall abutting the eastern corner encloses the rear garden.

Setting

The arch and lodge form the easternmost entrance to the Downhill estate. A bitumac drive descends from the slip road, enclosed to the west by a retaining wall built in vermiculated sandstone ashlar. The drive continues to the north side of the arch through landscaped gardens, providing public access to the Downhill estate. To the west of the arch is a bridge over an estate road, constructed from coursed rubble with rock-faced voussoirs and quoins. The bridge soffit is lined with bricks, and its parapets comprise a mixture of sandstone blocks and in-situ concrete. This bridge formerly carried the Coleraine Road before it was realigned.

The arch and lodge share the slip road with the Downhill outbuildings to the east and the kennel keeper's house to the north.