Mold Castle is first mentioned in 1146 and is an earthwork castle set upon and formed from a natural hillock.
On the northern side is a motte, c.57-62m in diameter and 10-14m high with a c.20m diameter summit upon which traces of masonry have been noted.
To the south are two rectilinear enclosures defined by c.10m scarps, c.64m N-S by 52m and c.32m NNE-SSW by 30m, respectively. A counterscarp survives only on the NW.

Since 1792 it has been set in a garden and modified by the construction of a bowling green, tennis courts and a Gorsedd Circle.

J.Wiles, RCAHMW, 21 November 2002

Bailey Hill is an extensive motte and bailey castle, its massive earthworks scarped from a prominent and steep-sided glacial esker at the northern edge of the medieval borough of Mold. It now lies within a 19th-century municipal park, and this has resulted in considerable alterations to the earthworks, although their overall form is easily discerned.

The monument comprises a very large motte with two baileys in line along the ridge to the S and a probable third to the N. The motte rises up to 12m above the inner bailey to a summit approximately 20m in diameter, now ringed by an intermittent low bank which may conceal the remains of walling. Rubble footings exposed in erosion scars below the summit may relate to the park. There are now no signs of a ditch, other than a short length around the north-west base of the motte. Modern concrete steps have been cut into the E face of the mound from the now rectangular inner bailey, most of the interior of which has been dug out or levelled into a bowling green with a pavilion formerly occupying a raised terrace to the S. Beyond this a substantial ditch, disfigured by recent paths and concrete revetments separated this from a second bailey on lower ground at the point of the ridge. This is now rectangular in plan but has clearly been levelled and modified to support former tennis courts. A smaller triangular platform of land at the point of the ridge to the N of the motte now supports a 20th-century Gorsedd circle but is likely to represent the modified remains of a third bailey. Whilst no substantial walling is visible today Bailey Hill is likely to have been a masonry castle and is mentioned in documents until the later 13th century. A series of large corbels and heads set into the garden wall of Tan y Coed to the SW of the scheduled area may come from the castle or an earlier phase of the parish church. The monument is of national importance for its potential to enhance our knowledge of medieval defensive and domestic structures and is likely to retain evidence of associated material culture. Mold or Gwyddgrug was an important castle and the administrative centre of a Marcher Lordship, the impressive and complex earthworks reflecting this status.

First mentioned in 1146, it probably dates to the early years of the Norman conquest, subsequent documentary references indicating several episodes of destruction and rebuilding. In spite of later landscaping, large areas of the site retain considerable buried archaeological potential, the historic record raising the possibility of multiple periods of timber and possibly masonry construction.

Cadw scheduled monument listing description,