Mounie Castle is a good example of a Laird's house.  It was small fortalice of the Setons originally constructed in the mid 16th century, it was restored in 1898. Mounie was a property of the Setons, but was sold to the Farquhars in 1634. Thereafter, it was passed on to the Hays of Arnbath in 1701. It was later recovered by a branch of the Setons of Pitmedden, who later sold it in 1970. The castle is private.

The building conforms to the T-plan with a long main block of three storeys running N to S, and a circular stair tower projecting westwards midway along the W front. The walling, now harled, is plain and roughcast and the gables crowstepped. The modern wing, attached to the SW, is actually a separate building extending from the NE.  A rectangular dovecot dated 1694 at Mounie was restored by Sir Robert Lorimer as a garden house in 1898, although no dovecot features survive.  Mounie is still in use as a private residence.