Argoed Mill Old Post Office

This is an asymmetrical group of buildings dating from the 18th and 19th centuries, comprising a mill, a cottage, and an old post office. The buildings are situated alongside a former head race.

The two-and-a-half storey mill is constructed of rubble stone with dressed stone detailing and a slate roof. It has arched openings with prominent keystones. The central entrance now has a replacement door set under a stone lintel. Adjacent to the left is a replacement segmental-headed window, and to the right is a wide arch leading to a through passage. The upper storey features central boarded doors incorporating glazed panels, and three-light windows to the left and right. A blocked loft opening is visible in the right gable end, positioned above the roof of Mill Cottage. The left gable end contains the wheel chamber, which has a later roof and doorway added, resulting from its conversion to electricity generation.

The rear elevation of the mill shows a wide passage archway to the left, with two blocked doorways to the right. In the upper storey is a three-light segmental-headed window to the left. A lean-to structure is present on the right, featuring an opening with a segmental tooled lintel and a corrugated iron roof, built against a stone wall that formerly supported the head race. Adjoining the lean-to is a corner brick fireplace belonging to a now-demolished range, also built against the head race wall. The head race wall contains a round arch with freestone voussoirs and keystone inscribed 1848.

Mill Cottage is set back from the mill and is a two-storey, two-window cottage constructed of rubble stone with dressed stone detailing, a slate roof, and a brick stack on the rear slope. Openings have segmental heads with keystones. The central boarded door has a glazed panel and a two-pane overlight. To the right and left are three-light windows, with the right-hand window being shorter. The upper storey contains two-light small-pane windows. The rear elevation has added lean-tos to the right and left. The upper storey has a two-light small-pane casement window to the left, along with similar, yet single-light windows, centrally placed and to the right. The right gable end, positioned behind the mill, is built of brick.

The Old Post Office is set at a right angle to Mill Cottage and is wider. It is a two-storey, three-window house constructed of rubble stone with tooled flat arches and keystones, larger tooled quoins, a slate roof with projecting eaves, a stone stack to the right, and a roughcast stack to the left. The symmetrical south-facing front has a central entrance with a boarded door incorporating a glazed panel, flanked by two-light casement windows. A George V letter box is located beneath the left-hand window. The upper storey has replacement windows in original openings. The left gable end is slate-hung and includes two two-light small-pane casements under segmental heads in the upper storey. The right gable end features a small window lower down on the left side, a two-light upper-storey casement window, and an added lean-to on the right.