Work on Chirk Castle is thought to have commenced in the last decade of the thirteenth century following Edward I's grant of the Lordship of Chirkland to Roger Mortimer. The intended plan of the castle appears to have been larger than actually executed, based on a north to south axis with circular corner towers and semi-circular towers at the midpoints of the northern, eastern and western curtain walls. With a central gatehouse sited in the southern curtain wall, it would have had affinities with the Edwardian Castles of similar date at Harlech and Beaumaris. However, the eastern and western curtains walls appear to have been only partially completed as do the towers which rise no higher than the curtain walls.

The castle suffered damage in the 1640s during the Civil War and again in 1659 when General Lambert moved against Sir George Booth's Cheshire rising. After the war the castle was extensively restored, and surviving features of the seventeenth century include a long gallery which has woodcarving of 1678 by Thomas Dugdale. Later alterations and additions which contributed to its evolution into a magnificent country house include those of Joseph Turner in the 1760s and 70s, those of A.W.N. and then E.W Pugin in the 1840s and 1850s, and those of Sir Arthur Blomfield in the 1890s. The property was owned by the Myddleton family from 1595 until it was purchased by the National Trust in 1978. The castle is surrounded by extensive gardens and parkland, landscaped by William Emes from 1764. The park gates of 1719 (NPRN 26957) are particularly elaborate and originally stood at the entrance to the forecourt before they were moved to their present position in 1888.

Gasworks were built to supply Chirk Castle and the Estate. Located NW of the Castle. A drawing of the gasworks, with its three retorts survives and dates to 1857, attributed to the engineer Robert Roberts. A building (Gashouse) flanked by two gasometers is marked on the 1899 1:2500 OS map (present but unmarked on the 1873 OS map). There was an additional gasometer marked SE of the gasworks on the 1899 OS map. The features were present on OS maps until 1954. The gas would have been used to light the castle and wider estate buildings with gas.

RCAHMW, 15 April 2008.