Sir James Balfour of Pittendreich extended the castle in the late 16th century, adding a curtain wall with a corner tower, and other outbuildings.
[6] An Act of Parliament in 1600 made Michael Balfour wealthy, directing landowners and people of standing to buy armour from him, for defence musters.
Escaping from Edinburgh tolbooth, Balfour joined the Jacobite cause, proclaiming the 'Old Pretender' James Stuart king at Lochmaben, and fighting in the 1715 rising.
It is now a Scheduled Ancient Monument[8] in the care of Historic Environment Scotland (no entrance charge; key available from nearby house at all reasonable times).
In the north-west corner, the original tower house survives largely intact (though one of the first floor windows has been greatly enlarged) to three storeys and a garret in height.
With its string-course, hood-mould over the gateway and moulded surround formerly containing a heraldic panel, this wall is an excellent example of small-scale but refined architectural sophistication of its period in Scotland (probably contemporary with the round corner tower).