Situated at the bottom of a NW-facing slope of the Tara ridge. The Dillon family have been in Ireland since 1185 and were settled principally around Drumraney (WM023-036----) Co. Westmeath, although scions of the family created dynasties in Roscommon in the sixteenth century based on their castle at Loughglinn (RO020-003001-). The family were also successful at filling many ecclesiastical posts and marrying into the gentry families of the Pale. Around the second quarter of the sixteenth century Sir James Dillon, the third son of Robert Dillon of Proudstown, married Jane Rivers, the heiress of Riverstown (ME031-031001-), and this and other properties passed to the Dillon family (Conwell 1873, 372-79). Thomas Dillon of Ryverston was a juror in 1540 (White 1943, 17). According to the Civil Survey (1654-6) Andrew Dillon of Riverstown owned 320 acres at Riverstown in Skreen barony in 1640, and the property included ‘a ruinated castle’ (Simington 1940, 71). Andrew also owned property at Castletown Tara (ME031-016----).
This is a four storey tower house vaulted over the ground floor with projecting square corner towers at every angle except the N. The W tower (ext. dims 3.65m NW-SE; 2.05m NE-SW) projects SW and contains a newel stairs, and the S tower (ext. dims 1.9m NW-SE; 1.55m NE-SW) contains garderobes and projects SW. The tower at the E angle projects SE (ext. dims 3.9m NE-SW; 2.75m NW-SE) and had had no special function. The original pointed entrance on the NW wall leads through a lobby protected by a murder-hole and an inner pointed doorway to the ground floor chamber (int. dims 5.3m NW-SE; 4.5m NE-SW) with a NW-SE barrel-vault. There is a blocked or robbed light on each wall and a lintelled doorway leads to the E tower, which is rebated at every level to support three upper floors. From the entrance lobby a short passage leads to a newel stairs in the W tower and the first floor over the vault that has robbed windows in the NE and SW walls and a fireplace on the NW wall. There are corbels in the NW and SE walls to support the second floor. The second and third floors are inaccessible now and obscured with ivy, but repeat the pattern of the first with large windows. The parapet does not survive, but the corner towers rise above the surviving walls of the main structure. A stone house (ME031-031002-) is attached to the NW, and the original doorway of the tower house leads directly into it.
The above description is derived from the published 'Archaeological Inventory of County Meath' (Dublin: Stationery Office, 1987). In certain instances the entries have been revised and updated in the light of recent research.
Compiled by: Michael Moore
Date of revision: 6 July 2016
Description Source: National Monuments Service, Department of Arts, Heritage Regional, Rural and Gaeltacht Affairs.