A New History of Aberdeenshire, Alexander Smith (Ed), 1875
This parish originally formed part of the parish of Peterhead, and was disjoined from it, A.D. 1619 or 1620. The church was for some time termed "the ower," or "upper kirk of Peterugie, or Peterheid." Soon after it was constituted into a parish, it was called Longsyd, from the name of the farm on which the church was built.
The parish is bounded on the north by Hythie in Old Deer, and Kininmonth in Lonmay; on the east by St. Fergus and Peterhead; on the south by Cruden; and on the west by Old Deer.
The greatest length of the parish, in a direct line, from the hill of Torhenry on the south, to the Lonmay boundary on the north, is a little more than 8 miles; the greatest breadth, in a direct line, from Downiehills in Peterhead, on the east, to near the Mintlaw Railway Station, on the west, is 6 miles; and the whole area is computed to be 16,894¼ acres.
The general appearance of the surface of the parish is distinguished by large tracts of flat land, and many fine undulations which scarcely can be called hills, if we except the hilly ridges lying along the Peterhead and Cruden boundaries. North of the Ugie, and the north branch of that river, are the Outhills of Rora, and the moss of Fortry, which is perhaps the most extensive tract of peat moss within the County. Between the Ugies there are the Ardlaw-hill woods, and the long broad ridge of Auchtydonald, with the village of Mintlaw on its western slope, and the Longmuirs on the north. South of the Ugie, on the western division, are the green-hills of Inverquhomery, Ludquharn, and Lenabo. On the north-eastern division, the surface is comparatively flat, but undulatory. The village of Longside, with the church, occupies a central position in the parish, and the church stands about 80 feet above sea level. The Cairngall granite quarries are about a mile east of the village, and stand at an elevation of 152 feet above sea level; the lowermost point on the Ugie, bordering with St. Fergus, is 40 feet; and the highest point in the parish, on the south branch of the river, above the Ellon and Fraserburgh road, is about 80 feet. In the east and south-eastern parts the surface presents a more hilly appearance. Here are the Meikle and the Little Dens, the Toddle-hills, and the hill of Cairn-catta, which is 312 feet above sea level, and forms the northern point of the long ridge of the bleak mossy hills of Torhenry, which bounds the parish with Cruden on the south, and the highest point on this ridge is 464 feet above sea level.
The names of places are in general derived from the Gaelic, though some of them may have been borrowed from the language now spoken. Cairngall is derived from the Gaelic, Carn-a-gail, which signifies "the cairn of the strangers," and probably refers to an invasion and battle with the Danes, and to the place where the slain had been buried; Cairn-catta, Carn-a-cath, signifies "the cairn of the battle;" Torhenry, Torr-an-righ, means "the King's hill"; Ludquharn, Leothad- chairm, signifies "the slopes of the cairn;" Ardlaw-hill is derived from Ard-laoi, or laoigh, and signifies "the height of the deer;" and Fortry is from Forthuir, or Foirthir, which signifies "the further or more remote place."
[A New History of Aberdeenshire, Alexander Smith (Ed), 1875]