Grotto about 30m to the south east of Dewstow House

Cadw's description

Location

In Dewstow about 1km north of the centre of Caldicot and situated on the north east side of Dewstow Road.

History

The Dewstow estate was bought in about 1890 by the agriculturalist Henry Oakley (died 1940) who was mainly responsible for laying out the very elaborate gardens in the years round about 1900. He may well have been influenced in their design by E J Lowe (died 1900) who lived at the nearby Shirenewton Hall and was also a fern grower. The underground gardens, constructed mainly of concrete block, brick and artificial stone (perhaps Pulhamite), are large and remarkable. The three surviving areas are listed separately.

Exterior

It is approached from the north down cement steps through a rough artificial stone arch. It is approached from the south through a small roughly circular rockwork area with two pools in the artificial rock floor and no roof. Steps lead down from ground level to another rough arch.

Interior

The steps lead to a winding passage lined with artificial rockwork. In the floor of the passage is a narrow rill, which widens into a pool in the central chamber. There is no top lighting, only an occasional hole in the roof to let a small amount of light enter; otherwise this area is completely dark. There are side chambers with fantastic forms and stalactites.

Reason for designation

Included as the garden features of an early C19 villa with well preserved character which was occupied for a long time (c1890-c1940) by Henry Oakley, a well known horticulturalist and breeder of shire horses. The garden is principally his work and includes these exceptionally fine and well preserved grottoes from about 1900 which were designed for the growth and display of ferns, an Oakley specialism. It is highly graded for these reasons.