South Block, Stables, Harlawhill House, Prestonpans

South Block, along with the stables, forms part of Harlawhill House, located in Prestonpans. The original house dates back to the 17th century, with a later 17th-century tower added to the front. An east wing and stables were built in the late 18th century. The original house was essentially a two-story, three-bay structure, with the east wing having similar proportions. The building is constructed from random rubble with raised margins, harled, and gabled. The southern wing collapsed due to mining subsidence in 1968.

The west and south wings feature a north elevation that is three bays and irregular. A door is located on the eastmost bay on the ground floor; the remaining bays are blank. An ogee-roofed tower with a finial projects from the central bay, featuring a single window off-centre to the west at the first floor, and a bipartite window and a single window at the first and second floors respectively, to the north. This tower is flanked on the east by an advanced gabled tower with a string course; its doorway has a plain classical architrave, a four-panelled recessed door, and a segmental arched fanlight above. A single window is located at the first floor. The south elevation is asymmetrical, with two windows on both the ground and first floors, and a tripartite canted dormer in the roof space. The south wing is largely collapsed, but still incorporates a rear door in the west angle of its return, as well as vestigial window openings. A small window is present in the loft on the west elevation.

The east wing has a symmetrical north elevation with three bays and three windows on both the ground and first floors. Its south elevation is now blank, except for a small window to the west on the ground floor.

The windows are timber sash and case, originally 12-pane, although some on the east wing have been replaced with plate glass. The roofs are covered with graded Scotch slate, with a crowstepped gable at the west end. The east wing features ashlar skewbacks and rolled skewputts. The stacks are largely rendered and deteriorating, with two on the gables, one on the ridge, and one on the rear wall of the west wing. The cans are irregular and mostly missing.

The interior, last viewed in 1996, contains many original, although plain, features of interest.

The stables are comprised of two symmetrical, two-story blocks positioned behind a high west boundary wall, surrounding a courtyard enclosed by a brick wall to the east. Each block has a door and window on the ground floor, and two windows on the first floor, facing the courtyard. Single-story brick lean-tos extend from the east side of the blocks. The windows are timber sash and case with 12 panes, and the roofs are piended in graded Scotch slate. A high boundary wall in random rubble with an ashlar cope defines the west edge; a depressed arch with impost blocks and raised margins provides access to the stable courtyard, flanked on the left by a pedestrian doorway. A small window is located on the upper level of the southernmost stable block. All doors and windows are shuttered with plain timber boarding.