In 1415 there were about 78 peel or pele towers in Northumberland. These towers were essentially private fortifications for protection in the event of Scottish raids – or neighbours you didn’t necessarily agree with. The idea was that you could secure your family and portable valuables until it was safe to emerge or help arrived – beacons were kept on the top of the towers which could be lit to summon help and to worn the surrounding countryside of danger. 
Peel towers were an architecture that resulted from the Scottish Wars of Independence. Some of the peel towers were not ordinarily used as dwellings – rather they should be considered refuges in times of trouble whilst at the other end of the spectrum places like Aydon Castle near Hexham resemble castles.
Preston Tower was built by Sir Robert Harbottle at the end of the fourteenth century. Sir Robert was a man of his time. He was part of the affinity of Sir Mathew Radmayne of Levens and rose in Redmayne’s service. When Harbottle murdered a man in Methley in Yorkshire in 1392 it was Redmayne and his successor who secured Harbottle’s pardon.
You’d have thought that Harbottle would have kept his head down but it wasn’t long before he came to the attention of the law once again when he took part in a raid on the Yorkshire property of Isabel Fauconberg stealing her property as well as the property of her tenants. A commission was set up to investigate but somehow or other Harbottle escaped the consequence of his crimes once more.
Henry IV, having taken the crown from his cousin Richard II, made him constable of Dunstanburgh Castle in 1399 – clearly not having read his cv beforehand. He even managed to acquire one of the wardenship of the east march – essentially turning Harbottle into the law. Perhaps it’s not surprising that since he did so well from the Red Rose monarchs that Harbottle was loyal to both Henry IV and Henry V even when the Percy family rebelled against them. Having bagged himself an heiress in the form of Isabel Monbourcher, Harbottle had risen from henchman to man of wealth and influence. When Hotspur rebelled against Henry IV, Harbottle was able to claim a better share of his wife’s inheritance – so it would appear that luck was on his side as well.
In between times Harbottle had served in Henry IV’s army in 1400 against the Scots and became a member for parliament. In short he had become part of the gentry in the north and had a good stout peel tower to prove it.
Preston Tower has walls which are over two metres thick, is three storeys high and has rooms off the main chamber at each level. It was described by Pevsner as one of the best bits of medieval architecture in the country.
https://www.historyofparliamentonline.org/volume/1386-1421/member/harbottle-robert-1419