The group comprises estate papers relating to the administration of the Garn estates, mainly in the parishes of Denbigh, Henllan, Llanefydd, Llanrwst, Nantglyn and St Asaph in Denbighshire, Rhuddlan, Flintshire, and Caerhun, Caernarfonshire. They include rentals, 1658-1784, and other estate management papers, 1708-1912, title deeds, 1572-1903, maps and plans, 1776-1866, and domestic management papers, 1725-1885.

Records relating to the parish of Cwm, Flintshire, including a transcript of the parish register for the years 1727 to 1763, a partial transcript of the register for the years 1763 to 1791, and details of the number of communicants for the years 1774-1786 and 1796; copies of a description of part of the manor of Rhuddlan, 1808, and of the boundaries of the parish of Newmarket, 1813, both by John Calveley; a description of the boundaries of the franchise of Rhuddlan by John Matthews, 1807.