Hardrigg Hall Farmhouse, with Tower, Barn and Stables Adjoining

Hardrigg Hall Farmhouse is a 19th-century farmhouse with an adjoining 14th-century fortified tower, barn, and stables. The tower, constructed for the Southaik family, features very thick walls made of large blocks of pink and grey sandstone and is currently roofless. The farmhouse has similar sandstone rubble walls, some of which incorporate reused stone from the tower, and is topped with a graduated greenslate roof and banded sandstone chimney stacks. The barn and stables share the same wall and roof construction.

The farmhouse is two stories high and has three bays, with the former three-story tower on the left and a three-bay barn on the right. There is also a rear right-angled extension that combines domestic and stable/barn functions, creating an overall L-shape. The tower has partial remains of three walls, with a staircase loop and a small upper-floor medieval window visible on the right return wall. The farmhouse features a central 20th-century door set in a 19th-century gabled stone porch, along with sash windows in raised stone surrounds. The barn has a central partly-blocked doorway and a loft doorway, flanked by ground-floor casement windows. The extension includes sash and casement windows in raised stone surrounds, with external stone steps leading to the loft doorway on the left return wall.

Inside the tower, the exposed interior reveals the remains of a vaulted basement, an angle newel staircase, and a shouldered-arched doorway in the basement. There is also a round-arched doorway that is now blocked by the farmhouse's gable wall, along with two additional round-arched doorways above. The tower contains medieval fireplaces on two levels and remains of three splayed windows in each wall, although it is now a stable ruin.