The Royal Commission on Ancient and Historic Monuments describes a bastle as:
‘Fortified’ because in the unregulated border between England and Scotland in the latter half of the 16th century the plunder of farms for livestock and goods was rife. The state could not offer protection therefore one had to protect oneself either by paying blackmail to the appropriate ‘godfather’ or by the possession of a strong house.
The bastle proved the perfect solution. Simpler and cheaper than a tower, the bastle's thick walls and secure entry prevented the loss of livestock and lives.
Cattle were kept in the basement accessed by a dedicated door. When closed from the inside the occupants could ascend via a trapdoor to the living chamber above whose own dedicated entry was only accessible from an outside fore-stair. The roof space, reached by a ladder, would have been a loft lit by a single widow in the gable. Thus secure, the occupants could ‘sit it out’ until the raiders had, hopefully, moved on at dawn.
Bastles tended to occur in clusters so help could be close at hand. So close, indeed, that neighbouring bastles were often within sight. However, they could be taken. A common ruse was to climb on to the roof and attempt to break through. If this proved impossible an alternative was to ‘lay fire’ to the lower door to ‘smoke out’ the inhabitants crouched inside.
That bastles were successful is proved by their number – some 700 or so being recorded of which the vast majority are to be found in the English northern counties.
Article by Scottish Castles Association member Brian McGarrigle.