St Anne's Tunnel West Portal (MLN111648)

St Anne's Tunnel West Portal is a Grade II* listed structure made of Pennant stone throughout. The stone is squared and coursed at the tunnel portal, side tower faces, soffit, and irregular supporting buttress, with ashlar used for all dressings, voussoirs, copings, crenulations, machicolations, and quoins.

The design features an asymmetric composition with a round arch spanning 30 feet (9 meters). This arch is made up of plain double voussoirs, set back and chamfered, and it terminates at the base with large chamfer stops. Below the arch, there are plain spandrels beneath double-step corbelled false machicolations, which are supported by pointed gothic arches. These arches lead up to an embattled parapet with profiled copings that slope down towards the track.

To the north (Down), there is a square, battered tower with crenellations that match the parapet. On the south (Up) side, the portal face is adjacent to the rockface, and free-form rubble buttresses are attached to support the tumble-home bedrock.