[1] It is located twelve miles (19 km) south-east of Edinburgh,[2] to the east of the village of Borthwick, on a site protected on three sides by a steep fall in the ground.

The castle was built at the site of an earlier structure, and it remains the Borthwick family ancestral seat.

[citation needed] Sir William Borthwick, later the 1st Lord, obtained from King James I on 2 June 1430 a licence to erect on the Mote of Locherwart, a castle or fortalice.

[7] The well-preserved medieval effigies of the builder and his lady can be seen in the nearby parish kirk of St Kentigern, which retains a 15th-century aisle also probably built by him.

In June 2013, the castle closed for extensive refurbishment, and once again opened as an events venue in September 2015.

Apart from the large cannon scar on one face, the walls, built of fine sandstone ashlar, are virtually complete, and very unusually, none of the original narrow windows have been enlarged.

[18] Borthwick Castle is the setting for local ghostlore stories, one of which features Mary, Queen of Scots.