East Tunnel, Tunnel Brae, Castlerock, Co Londonderry, BT51

One of a pair of railway tunnels located between Coleraine and Limavady Junction, built c.1853. The East Tunnel runs through a headland in a straight line for 614 metres (672 yards) from the west end of Castlerock to the east side of Portvantage Glen. East portal The portal at the east end of the tunnel comprises a semicircular-headed arch with rusticated and margined abutments quoins and voussoirs. The latter step into the spandrels and have a plain keystone. The spandrels and parapets are of roughly-dressed and coursed basalt blocks. A dressed horizontal string course runs along the base of the parapet. The top of the parapet is sloped to follow the line of the road which crosses the road at this point. It is coped with irregular stones but has been heightened with mass concrete which also follows the gradient of the road. A small enamel plaque at the left end of the string course notes that this is bridge number 196. A modern metal sign in front of the portal notes the tunnel as 614.05m long, with refuges every 50m along it on its seaward side. Galvanised metal poles runs up each side of the portal; they were probably for electric cables, but now appear to be redundant. West portal The western portal, at the Portvantage Glen end of the tunnel, differs only slightly from its eastern counterpart. Its spandrel is of random basalt blocks and the string course over is chamfered along its top edge. There is a low parapet over, of coursed basalt blocks, with projecting basalt coping blocks. Sections of the parapet and coping have been repaired with mass concrete. The cliff directly above the portal has been gunited (sprayed concrete) and steel wire netting has also been affixed to its face to prevent rocks falling on to the line. From the west portal, the railway line continues along a 120m long embankment just above the rocky shore to the east portal of the West Tunnel (HB03/12/031B). Air shaft The 25-inch OS maps show an air shaft approximately 280m in from the eastern end of the tunnel. Its top end was originally on open ground but is now subsumed into a caravan park. It would have vented the smoke from the steam trains originally. It is now redundant and has been capped over with reinforced-concrete, with a small manhole for access should the need arise. Setting The tunnel runs through a high sea-washed headland to the east of Castlerock and emerges at the tranquil Portvantage Glen. The eastern part of the headland under which the tunnel cuts through is occupied by a caravan park. Schedule: Basalt abutments and linings Brick soffits