Carolside, a mansion, with a fine deer-park, in Earlston parish, SW Berwickshire, on the left bank of Leader Water, 1¼ mile NW of Earlston village. It is a seat of Donald Jas. Mackay, eleventh Lord Reay since 1628 (b. 1839; suc. 1876), he having married in 1877 the widow of Alex. Mitchell, Esq. of Stow and Carolside, who owned 2455 acres in the shire, valued at £2635 per annum.

(F.H. Groome, Ordnance Gazetteer of Scotland (1882-4); © 2004 Gazetteer for Scotland)