SLANE, a post-town and parish (formerly a parliamentary borough), in the barony of SLANE, county of MEATH, and province of LEINSTER, 6 3/4 miles (W. S. W.) from Drogheda, and 22 (N. by W.) from Dublin, on the mail coach road from Dublin to Londonderry, and on the river Boyne; containing 2516 inhabitants, of which number, 896 are in the town. This place is of very high antiquity, and in the earliest ages of Christianity was the seat of a small diocese, of which St. Eirc, who had built himself a hermitage, was consecrated first Bishop by St. Patrick, and died in 514. On the neighbouring hill an abbey for Canons Regular was founded at a very early period, into which the young Dagobert, king of Austrasia in France, who was banished from his own country when only seven years of age, was received in 653, and educated; he continued to reside in it 20 years, till recalled to France and restored to his throne. This establishment was many times plundered and the monks massacred by the Ostmen of Dublin, to whose ravages it was peculiarly exposed; in 1172 the town was sacked and burned by Dermod Mac Murrough and a party of the English; and it was again plundered by the English in 1175, from which period it seems to have continued in decay till the year 1512, when it was restored by Sir Christopher Fleming, Lord of Slane, who placed in it two friars, who then resided in the hermitage of St. Eirc. On the settlement of the English in Meath, the town became a borough, and in the reign of Hen. VI. ranked as one of the middle class. The Fleming family having been engaged in the civil war of 1641, the estate escheated to the Crown, and subsequently became the property of the Right Hon. William Conyngham, ancestor of the Marquess Conyngham. The place is within four miles of Oldbridge, where the battle of the Boyne was fought; and the bridge of Slane has been on many occasions considered and defended as a pass of importance. The town is pleasantly situated on the northern bank of the river, which is navigable from its estuary at Drogheda up to Navan: it consists of 143 houses, which are chiefly modern and of neat appearance, and the richness of the surrounding scenery renders it one of the most attractive places in the county. The market has been discontinued: fairs for cattle and pigs are held on the 2nd of April, June, and Sept., and on Nov. 8th; petty sessions on alternate Fridays; and it is a chief constabulary police station.

The parish comprises 5855 1/2 statute acres, for the most part of indifferent quality: there is no bog, except in the vicinity of the town. About 30 years since coal-works existed, but they proved unproductive, and were abandoned. On the river, adjoining the town, are very extensive flour and corn-mills, the property of Blayney Townley Balfour, Esq., worked by seven pairs of stones; they have an excellent supply of water and are capable of grinding 1000 barrels of wheat weekly. To the west of the town is Slane Castle, the seat of the Marquess Conyngham; it is a spacious and elegant structure, in the later English style of architecture, with embattled turrets and pinnacles, comprising part of the ancient castle of the Flemings: it is beautifully situated on an elevated site, on the steep banks of the Boyne, and surrounded by an extensive and richly wooded park of about 900 statute acres, through which that river winds: the interior of the castle is very handsome, particularly the circular room, which has a splendid groined ceiling, and is adorned with some good paintings, among which is a fine picture of the battle of the Boyne, and Sir Thos. Lawrence's portrait of Geo. IV., in his robes, who visited the Marquess here in Aug. 1821. The living is a rectory, in the diocese of Meath, and in the patronage of the Crown; the tithes amount to £407. 15. 6. The glebe-house was built in 1807, at an expense of £1046, British currency, which was defrayed partly by a gift of £100, partly by a loan of £500, from the late Board of First Fruits, and the residue by the then incumbent. The glebe comprises 12 acres, and, with some houses on it, is valued at £41 per annum. The church is a neat edifice, with a handsome steeple, after a design by Johnston, erected in 1712; it was enlarged in 1830, by aid of a loan of £200 from the same Board, and has been recently repaired by a grant of £134 from the Ecclesiastical Commissioners. In the R. C. divisions the parish is the head of a union or district, comprising the parishes of Slane, Gernonstown, Rathkenny, Stackallen, Dunmoe, and Fennor, and containing three chapels, one in Rathkenny, and two in this parish, of which one "is a neat structure, situated in the town. About 180 children are educated in the public schools, of which the parochial schools are under the trustees of Erasmus Smith's charity; one for females is supported by the Dowager Marchioness Conyngham; and the other is a national school. There is also a private school, in which are about 150 children. Of the ancient castle of Asigh, on the right bank of the Boyne, there remains only a square massive tower, commanding an extensive southern view of the hills of Taragh and Skryne: about 30 yards northward are the ruins of a small chapel. There are the ruins of a monastery and college on the hill of Slane; and of a hermitage in the Marquess Conyngham's park. In the vicinity of the town are the ancient mounts or tumuli of New Grange; the principal is a large mound of earth, 70 feet high and 300 feet in circumference at the top, covering an area of an Irish acre; it is irregular in its form, and was surrounded at the base by a circle of huge upright unhewn stones, several of which remain. On removing part of the materials, in 1699, a large stone was found, covering the entrance to a gallery 62 feet long, leading to a central arched cavern with three offsets, forming together in their ground plan a rude cross; the entrance to the gallery is only three feet wide and two feet high, at first decreasing in breadth, and farther on formed of large upright stones on each side, with others extending horizontally to form the roof, which is high enough to admit of approach in an upright position; the dome in the centre of the cross is of octagonal form and about 20 feet high, with a coved roof formed of courses of flat stones successively projecting; in the right branch of the cross is a large stone vase, within the excavated part of which are two circular cavities of less than a foot in diameter; several of the stones are sculptured with rude ornaments and devices. When this cavern was first opened, two human skeletons were found entire, and also some horns and bones of deer. Slane gives the inferior title of Viscount to the Marquess Conyngham.  (Description from Lewis Topographical Dictionary) http://www.slanecastle.ie/concerts.htm