The walled garden was the site of a
real tennis court in the 17th century and was a bowling green by 1718. It then became an orchard; an example of an 18th-century
hypocaust (heated) wall still survives, where fruit trees would have been '
espaliered' (trained flat) against the warm brickwork. There are traces of the stoking chamber for this wall in a neighbouring garden. Roman and Norman remains lie deep beneath the lawn. The Nelson Garden commemorates Lord Nelson's visit to Monmouth on August 19, 1802, with
Sir William and
Lady Emma Hamilton on the occasion of their tour of the
Wye Valley. Having been entertained at the
Beaufort Arms, the party adjourned "accompanied by Colonel Lindsay to the beautiful summerhouse in his garden there to enjoy the refreshment of tea or coffee and to pass the rest of the evening in that charming retreat". Although the 'charming retreat' has vanished, in about 1840 the present Memorial Pavilion was erected, possibly to the design of
George Vaughan Maddox, the Monmouth architect. Being of timber, various parts have had to be replaced over time and it is not known how much of the current structure is original. "Lord Nelson's Seat" remains an attractive feature, bearing a plaque commemorating Nelson's visit. The
Royal Commission on the Ancient and Historical Monuments of Wales describes the summerhouse as "important and unusual." Until 1950 the garden was maintained by the resident managers of the adjoining bank (Lloyds Bank occupied 18 Monnow Street, a listed building). This changed when their families were allowed to live elsewhere, but the garden continued to be maintained by resident tenants. Thereafter the garden deteriorated, but in 1994 the Nelson Society and
Monmouth Archaeological Society, began restoration. In 1996 the
Welsh Historic Gardens Trust became involved and in 1997 set up a restoration committee to care for the garden. In 2001 the committee negotiated a 10-year sub-lease from Lloyds Bank, funded conservation work on the entrance tunnel, and installed a decorative iron screen to separate the garden from the rest of the bank property. ==Architecture==