Offham tramway tunnels, portals, parapets and retaining walls

The Offham tramway features two parallel tunnels that carry the track bed beneath the A275 road. These tunnels slope downwards from west to east at an incline of 1 in 3.5 and each measures 22 meters in length. They have slightly flattened semi-circular barrel vaults, separated by a 0.45-meter thick brick wall. The entrance at the west end is approximately 1.5 meters from the ground to the crown of the vault, while the east end reaches about 8 meters. The internal height is estimated to be around 2 meters from the track bed to the crown of the vault, although this measurement may be affected by a significant build-up of soil within the tunnels, especially at the west end where the clearance is notably reduced. The interiors are finished with lime wash or plaster rendering over red brick.

Above the tunnel entrances, the walls are battered at an angle of about 13 degrees from the vertical. The west end features red brick in English Bond construction, topped with a soldier course. This section has undergone repairs with mainly new bricks, alongside a few original ones.

At the east end, the central 1809 tunnel walls are constructed in header bond and supported by three later buttresses. The retaining walls flanking this central area extend to both the north and south sides and are of mixed construction, with some sections underpinned by concrete. The lower parts of the retaining walls are made of flint rubble and are believed to pre-date the tramway, as they are battered at a steeper angle than the tunnel entrances. The upper portion of the east face of the tunnel entrance and retaining wall features a later phase of brick construction in English Bond, topped with a thick parapet wall and a cement coping. Iron gates, marked with the date 1809, were added to the entrance of the east portal in 1994 by East Sussex County Council.