1430: In the Beginning
The castle was built in 1430 by Sir William de Borthwick, who was one of the nobles who volunteered as a substitute hostage for the ransom of James I of Scotland in 1425. Borthwick was given a special licence by King James I to build 'a castle or fortalice, to surround the same with walls and ditches, and to defend it with gates of brass or iron; and also, to place upon the summit defensive ornaments, by which is meant battlements and turrets.'
Having purchased the lands from Sir William Hay of Yester, Sir William de Borthwick built the tower to an impressive scale: 74 feet in length, 68 in breadth, and in height, from the area to the battlements, 90 feet. A contemporary source describes 'a great and strong tower within and without, and of great height, the wall thereof being above 15 feet in thickness towards the foundation.'
The walls are of hewn stone, and the knoll on which the castle is situated, is surrounded by a courtyard, enclosed and fortified by a strong outer wall. The Middleton Burn joins to form Gore Water - a tributary of the South Esk - surrounding the castle and contributing to its romantic appearance. The entrance from the outer court to the keep would have been by a stone ramp, linked with the gate of the tower by a drawbridge - a means of interior defence peculiar to castles of the 15th century. The battlements of Borthwick Castle also command some of the most beautiful views in the area.
The interior of Borthwick Castle has seen little structural alteration over the years. The Great Hall is on the first storey and is 40 feet long, with a music gallery perched above and a lofty roof. The roof and walls would once have been adorned with colourful paintings and motifs, with inscriptions including 'ye tempil of honour' and 'ye tempil of religion'. There are three sets of spiral stone stairs, giving access to the Keep's separate storeys, including a small room that is believed to have been the bedchamber of its most famous resident...Mary Queen of Scots.