Round about the beginning of the nineteenth century, the only communication routes entering 'Stevenstoune' (as it was then spelt) were rough tracks which became impassable to wheeled vehicles during inclement weather. Between 1810 and 1840 trade was at a low ebb in Scotland, due primarily to the Napoleonic wars and the civil war raging in America, when an embargo on trade between Great Britain and the United States was imposed. But in 1849 trade took a turn as far as Stevenston was concerned and the Glengarnock Iron Company built five blast furnaces on the foreshore to smelt pig-iron. The site was selected primarily because iron ore and coal could be mined extensively in the district.

At the turn of the nineteenth century, steel was coming into its own as a substitute for wrought iron and the pig-iron industry began to contract. The Stevenston Iron Works was at a disadvantage as the pig-iron produced at Ardeer was not quite the best for steel making due to the high incidence of impurities in the ore. Although there was plenty of iron ore in the district, particularly around Dairy, the ironmasters had to import ore from Spain and North Africa, particularly Tunisia, to enable them to compete with other pig-iron manufacturers in the county.

Iron ore was shipped to the port of Ardrossan and transported by rail to Stevenston. Merry & Cunningham Ltd., who had succeeded the Glengarnock Iron Company as owners of the works, decided, with a view to cutting the costs in importing iron ore, to undertake to build a quay running out into the Firth of Clyde for 300 yards from high water mark. The object in view was to bring the ore boats into their own pier as against the port of Ardrossan. They proceeded to dump their slag into the sea for that purpose and a promontory stretched for fully 300 yards out into the Firth. The project was fairly well advanced; piles were driven in at the extremity and for some distance, a concrete pier was laid down. The project was abandoned only after it was obvious to those concerned that during rough weather, no ship could tie up safely in such an exposed position. The remains of this quay are still to be seen and the area is still referred to as the ' slag point ' or ' old pier '. The blast furnaces were worked around the clock shifts and iron was cast three times in the twenty-four hours, each pig bar having 'Glengarnock' stamped along it. The old trade mark was continued by Merry & Cunningham until they went into liquidation in 1931. The works were dismantled shortly after, and finally razed to the ground in 1935, after being in existence for nearly ninety years.

The whole area was transformed by the public works contractors, Shanks & McEwan, and a beach holiday camp was laid out which had not a very long life as the war intervened and the camp was used as a military garrison for the duration of the last war. That camp, too, has now passed into oblivion.

The furnaces themselves stood on the ground immediately behind the present Trelawney Terrace and, as had been previously stated, there were five in number. To the immediate south was the ammonia works and to the rear of the only remaining vestige of the iron works, namely, ' Seamore House ', which today stands isolated, was practically in the centre of activity. Adjacent to it were the workshops of the craftsmen, namely the engineering, blacksmiths and carpenters' shops. Facing the front of Seamore House, which incidently was the home of the work's chemists and draughtsmen, was the laboratory and drawing office and a row of houses which housed the craftsmen and foremen, and known locally as the Chemical Row.

 A little more than 100 yards from the furnaces and pig-iron beds were the company's houses, which housed the furnace keepers and the other skilled workmen. They were built true to the tradition of furnacemen and colliers' rows. But, unlike most, instead of having a common green in the centre of the square, there was a pond of water; a man-made reservoir, where water was harnessed and stored with pipes leading to the works, and used for cooling the pig bars when cast, and damping the sand again for remoulding. To replenish the water in the pond, water was pumped from a 'weir' in the Stevenston Burn in the grounds of Ardeer Cottage which was originally the home of the iron works manager.

The remains of the pump-house is still to be seen and it is interesting to recall that this 'weir' was originally formed to carry the canal across the burn and on to Saltcoats harbour. It is worthy of note in passing that a firm favourite, but dangerous game of Stevenston boys was cooking potatoes in the hot sand between the pig bars when the furnace keepers' backs were turned. It is claimed that those who have never tasted potatoes cooked in that fashion have missed an excellent dish.

The fact that the pond, or reservoir, was in the centre of the square instead of the 'common green' was always a sore point with Ardeer Square residents, particularly latterly, when it was stagnant. An element of danger was forever prevalent through children of a tender age having a tendency to wander near the edge of the pond, and it was completely contrary to the public health interest.

Today, local housing, occupies the site.