North Sutor, Coast Battery

This underground radar station with three compartments, comprising an observation post, a receiving room and a transmission room, is situated amongst gorse, brambles and bracken at the edge of a cliff overlooking the Cromarty Firth, about 400m NW of the Counter Bombardment Observation Post (NH 86NW 9.08) and 1km NE of the North Cromarty Battery Site No.1 (NH86NW 9). It was serviced by two underground engine houses, which are linked to it by a network of open gullies from which electrical cables have been extracted.

The radar station (NH 82884 69806) measures 16.25m from WNW to ESE by 7.35m transversely within reinforced cast concrete walls up to 0.35.m thick and 2.8m high.

Externally, there is an ivy-draped stairwell to the WNW of the building, which is surrounded by a low parapet containing a broad flight of grass-grown steps leading down into the interior. Two abutting, flat overhanging grass- and moss-grown concrete roofs to the ESE cover the building – one overlying the receiving and transmission rooms, while the other, rising 0.23m above its neighbour, overlies the observation post overlooking the cliff. The former retains an arrangement of bolts on a low concrete plinth on the SSW, while the bolts of another mast base are situated 4.6m to its NNE. In addition, one circular vent is visible. The only other feature of the building that is visible from the exterior are the upper sections of a pair of thin buttresses against the NNE and SSW walls of the observation post provided to support the canopy.

A pair of double doors situated at the foot of the stairs has been removed leaving only their wooden frame, but these provided access to a corridor subdivided into an inner and outer lobby linking the three compartments within the building. The outer lobby measures 4.2m from WNW to ESE by 2.35m and 2.82m high. Its walls and the ceiling have been whitewashed and there is a wooden batten on the NNE wall retaining five wire coat hooks. The doorway to the inner lobby is situated at the far end, but double doors on the SSW provide access to the transmission room, although only one these remains in place. This room, which is littered with debris resulting from its abandonment, measures 4.25m square. It has a whitewashed ceiling and walls, but its principal features comprise three circular vents in the ceiling, a broad cable duct running down the WNW wall at the N corner which links with a network on the floor, wooden plugs and fixings on the walls for electrical cables and switchboards, long slit-shaped apertures in the ESE wall, with the most prominent positioned centrally just below the ceiling, and a sliding doorway at this wall’s E corner which provides access to the receiving room. The latter is rectangular on plan and measures 5.7m from WNW to ESE by 4.3m transversely. The floor is strewn with debris, but its ceiling and walls retain their whitewash. The most striking features of the ceiling are the presence of an iron plate with a large circular aperture for cabling passing down from the mast above, another plate with a small central spindle, a skewed arrangement of four metal bolts close by and three circular vents. Other elements include a network of cable ducts on the floor and a substantial metal fitting immediately below the position of the mast, a duct running from floor to ceiling in the ESE wall adjacent to the N corner of the room, a rectangular hatch permitting visual and verbal communication with those in the observation post, various fixings for cables and switchboards, together with vents just below the ceiling in the NNE wall, which also contains a doorway leading out into the inner lobby. This lobby measures 6m from WNW to ESE by 1.75m transversely and its ceiling and walls are also whitewashed. Its most significant features are the buttresses interrupting the corners of its SSW wall, which are fundamental to the structure of the building, but there are also two circular vents in the ceiling, a length of batten retaining four wire coat hooks on the NNE wall and the three steps leading up to a door on the ESE that provide access to the observation post. The latter, which measures 6.4m from WNW to ESE by 4.6m and 2.45m high, is whitewashed throughout, but heavily invested with ivy. The canopy above the observation window on the ESE is supported by two horizontal iron girders strengthened at each side by two shorter ones - the weight being carried by NNE and SSW walls which are buttressed on the outside. Ducts rising part way up the NNE and SSW walls originally led to switchboards and there are a number of additional fixings for electrical cables and equipment. Three square concrete pillars for a Position Finder are situated below the canopy on the NNE are connected to a duct in the floor running NNE.

The underground engine houses are of exactly the same design, with one being reserved as a backup in case of the other’s failure. Both are now deeply encumbered by bracken, brambles and gorse. One (NH 82862 69834) is situated 25m NE of the Radar Station and is orientated from NE to SW, while the other (NH 82857 69850) is situated 16m to its WSW and is orientated from NW to SE. They measure about 7m by 4m overall, but little is visible externally apart from their heavily vegetated flat, overhanging concrete roofs with a single capped chimney stack at one end for the escape of exhaust fumes and two stairwells at right-angles to one another containing steps leading down to the interior. The main steps at one end of the building descend to a double doorway, but the doors themselves are now missing. These provide access to a narrow, whitewashed corridor running at right angles to the stairwell. One end of this rounds a corner only to terminate abruptly, while the other passes through a wood and corrugated iron sheet-framed doorway to lead to the second stairwell at the side of the building. Immediately opposite the main entrance is a second double doorway with a step up providing access to the engine room. This measures 4.9m by 2.7m transversely within whitewashed walls 0.38m thick and 2.75m high. The plinth for the engine dominates the compartment, but it is positioned off-centre and measures 2.92m long by 0.87m transversely and 0.48m high. There is a cable duct high in one wall that leads down to the floor and to the foot of the plinth and there is an exhaust pipe in the rear wall behind the plinth. In addition, there are five circular vents in the ceiling arranged in a quincunx and rectangular vents just below the ceiling. Two of these pierce the wall through to the stairway at the side of the building where they are covered by metal grills.

A grass-grown building platform (NH 82857 69849), measuring 3.7m from NE to SW by 2.5m transversely, is situated 12m NNW of the more northerly engine-house. It may have been for a latrine and as the platform is cut back into the slope on the SW, this must have been entered from the NE.

The radar station was an integral part of the coastal defence system, as it was tasked with detecting and directing fire from the battery. It picked up the fall of shots in the sea by establishing the splashes in relation to the position of the ships under attack. The information was then transmitted back to the gun battery to increase the accuracy of the fire.

Visited by HES Survey and Recording (ATW, AKK) 30 May 2019.