In 1488, Helmsdale castle was built as a hunting lodge for land owning aristocracy by Margaret Baillie, Countess of Sutherland. The stone tower was the setting for an infamous murder plot with the perprtrators posioning the drinks of their unsuspecting guests. It is said that these tragic events inspired Shakespeare to write the play Hamlet.

The castle was knocked down around 1970 to make way for the new road bridge and all that remains of the castle today is a carved stone fireplace lintel, now in Timespan Museum. It bears a carved exhortation in Latin with the wise words “If you wish to be wise, I enjoin you to observe six things. What you say, and about whom, where, to whom, how and when.”