Tower Lodge and Glanusk Bridge (partly in Llanfihangel Cwmdu with Bwlch and Cathedine community)

Tower Lodge and Glanusk Bridge are situated partly in Llanfihangel Cwmdu, with sections extending into Bwlch and Cathedine communities. The bridge, dating to 1836, is a three-span flat-decked structure featuring wide segmental arches constructed from coursed grey rock-faced stone in large blocks. It has narrow voussoirs and a narrow string course with parapets above, built of smaller stone blocks with ramped copings. Each parapet displays a shield bearing the engraved date 1836. Large projecting cut-waters with pyramidal tops are positioned above narrow pilasters. The base of the north cut-water on the western side has been refaced with concrete blocks. Oval tie plates are visible through and flanking the pilasters. The bridge extends southward towards the lodge, which is positioned up the bank. An extension to the bridge contains a large circular opening with voussoirs, through which a cobbled trackway runs, with a further pattress plate to its north.

The Tudor-revival style lodge and gate-house is designed as a late-medieval fortified tower. It is a square, two-storey structure with embattled parapets and a high battered plinth, constructed from coursed grey rock-faced stone matching the bridge. At first floor level, a pair of string courses runs between a row of shields bearing coats of arms. Additional string courses are located below the parapet and at the top of the plinth. The lower storey contains a through-passage with basket arches in the north and south walls. The upper storey features flat-headed sandstone mullioned windows with hoodmoulds, each containing three round-headed lights with diamond quarries. These openings are flanked at ground and first floor levels by tall blind slits, with the exception of the south-east corner. The east side of the tower has a window to each storey, similar to the north and south sides, but with two lights, while the ground-floor window also includes a transom. A narrow slit is located at plinth level. The west side is similar to the east, but the windows have three lights, below which is a planked door leading to a basement room. The octagonal turret, which rises above the tower, also has an embattled parapet and tall narrow slits to each storey, except on the south and east sides where single round-headed windows are present.

Inside the gateway, arched openings match those on the north and south sides. To the west of the gateway is a small, featureless bay. To the east is a similar bay containing a planked and ribbed door under a segmental head, which provides access to the tower (which is not accessible). A similar door is located at the north end of this bay. The floor is of flagstone, and tierceron ribbed vaulting is present above the entrance gateway.