Trevor Old Mill

Tall, 4-storey tower-like building with single-storey lean-to extension to SE. Rubble stone throughout with squared quoins and segmental arches of stone voussoirs to windows and blocked openings. Gabled, slate roof with central projecting gablet (over hoist) on NE elevation, and stone chimney-stack at NW corner. Three-window range main front (NE elevation) has central doorway with modern porch hood and 6-pane double casement windows; first floor with central window and blocked openings on either side; 2nd floor with two casement windows; 3rd floor has central cantilevered metal balcony on wooden brackets, modern hoist door with iron plaque embossed '1848' above and two casement windows; four iron tie-rod bosses. Two-window NW and SE elevations; six iron tie-rod bosses to NW. SW elevation with two randomly placed casement windows on upper floors and arched opening above water-wheel axle at ground floor level.

Large diameter iron pitchback water-wheel with 12 paired timber spokes and wooden axle; iron cogged external pit-wheel. Masonry wheel pit recessed below ground level. Iron supply tank supported on iron half-trestle frame. Iron supply pipe supported on timber frame at water-wheel end by freestanding rubble stone pier.

Interior modernised but retains timber main shaft and iron spur wheel at ground floor. Dog-leg stone stairs to sub-rectangular basement with main shaft and iron cog-wheel.