Johnstone Castle belonged to the Houstouns of Milliken, who acquired the estate of Easter Cochrane in 1773. The original structure was substantially enlarged in 1771 and 1812 by George Houstoun, who had the structure remodelled in a castellated style complete with a turret at the left hand of the front elevation, possibly by the architect James Gillespie Graham.
The most notable features were barrel vaulted rooms in the ground floor. Externally in addition to the battlemented decoration there was a rope-styled string course. Although the castle and policies were considered particularly picturesque, the continued growth of the town of Johnstone reduced its size and the estate had largely disappeared by the start of the 20th century. Much of the house was demolished in 1950, and most of the remainder of the grounds was purchased by the local authority for housing in 1956.
Today all that remains is the central square tower along with a crow-stepped bartizaned section of an older date.
References:Rosenborg Palace was built in the period 1606-34 as Christian IV’s summerhouse just outside the ramparts of Copenhagen. Christian IV was very fond of the palace and often stayed at the castle when he resided in Copenhagen, and it was here that he died in 1648. After his death, the palace passed to his son King Frederik III, who together with his queen, Sophie Amalie, carried out several types of modernisation.
The last king who used the place as a residence was Frederik IV, and around 1720, Rosenborg was abandoned in favor of Frederiksborg Palace.Through the 1700s, considerable art treasures were collected at Rosenborg Castle, among other things items from the estates of deceased royalty and from Christiansborg after the fire there in 1794.
Soon the idea of a museum arose, and that was realised in 1833, which is The Royal Danish Collection’s official year of establishment.