In the late nineteenth century, the Hessilhead castle was already described as a ruinous and roofless castle. By 1956, The Royal Commission officially reported that the castle had been entirely demolished.

Early recordings claim that back in 1604, the castle was encircled by a large moat and built on a loch. The moat has long since been filled in and the loch drained. By 1747, maps show the castle named as “Heeselhead”, and located in a farming community called Hazlehead. Further reports at that time describe the castle as a 15th to 17th century keep, which coincides with records showing an expansion built onto the castle by Francis Montgomerie in 1680.

Hessilhead was once home to the family of Lord Glasgow and after they departed, a Mr. Macmichael in 1776, removed the roof and left the estate to go to ruin. Circa 1887, it was reported as being treated as a garden. James D. Dobie, a historian and author, recorded the plunderer of Hessilhead as Carmichael, who removed sellable materials from the estate and also took off parts of the stone walls, and also cut down and sold a large old Yew tree. In the 60s, the remains of the estate were demolished as instructed by Howie of Dunlop.

Dobie also wrote that at south of the ravaged castle, a person can create a singular echo, which plaintively and slowly repeats the voice only once, throwing a melancholy aura over the area.

Now, there is a wildlife rescue center at Hessilhead run by Andy and Gay Christie for over twenty years. They rescue and nurture abandoned and injured mammals and birds, and treat over 3000 animals annually. They even have a swan treatment facility, X-ray equipments and a surgery room, as well as a part-time veterinarian.