Abercarn Aqueduct and bridge (partly in Crosskeys Community)

The Abercarn Aqueduct and bridge, located partly in the Crosskeys Community, carry both the canal and the adjacent road across the Carn valley. The structure features a high abutment to the west with a relatively small tunnel for the stream. To the south, there is an extension of the abutment made of different later masonry, with both sections rising to form a low parapet beside the west side of the canal. On the east side, also constructed of later masonry, is the east tunnel portal, which does not align continuously with the higher roadside parapet.

The aqueduct masonry on the west side is primarily made of narrow coursed rubble, forming a massive retaining wall with ashlar voussoirs and tooled quoins. It has a segmental arched portal, with walls that project slightly on either side, leaving the central section, including the arch, recessed. The walls curve outward, with a sharper curve at the northern end. The southern end returns sharply, changing to rockfaced stone masonry. The parapets at canal level differ in appearance but are mostly covered in ivy.

On the east side, the portal is round arched, featuring deep narrow rockfaced voussoirs. Angled abutments with a heavy capstone, which is incomplete on the left side, are built against the archway, with the masonry bonded at the impost level. Above this is the roadside parapet made of rubble with rockfaced coping, marked by a boundary stone that reads 'Mynyddislwyn Highway District MR 1880'.