Building record 0420802015 - GROTTO, Grotto Lake, Stowe Landscape Garden

Grade II+. Three rough arches of stone with pebble lined basin, c1740 perhaps by Kent, romanticised and buried c1780. Interior: central vaulted chamber, with remains of tufa lining, niche in rear wall. Barrel vaulted side chambers and entrance passages (B14).
In the 1730s Lord Cobham hired William Kent, the landscape gardener and artist, to design a neo-classical grotto at the head of the Serpentine river. Kent created a square cross-vaulted chamber with a statue of Venus in a central recess, the water flowing through a series of basins into the river in a style reminiscent of early Roman grottoes to Venus. Originally used as a banqueting house for light refreshments, the grotto at Stowe was remodelled later in the eighteenth century with a covering of tufa and rockwork to give it the rustic and subterranean appearance by then fashionable for grottoes (B50).
An archaeological investigation was undertaken by the National Trust in March 2001 as part of the programme of restoration . Historical sources attribute the design to William Kent and the building to the late 1730s. It is believed to represent the face of Hades with River Styx flowing from the mouth. It was originally a free standing structure with a statue of Venus by Peter Scheemakers standing on a shell-embossed pedestal. The interior was changed by adding shell decorations, mirrors and glass fragments in 1740s. It was extensively remodelled in 1760s by adding side passages, the back of the building was buried and tufa attached to disguise all the stone and brick work. A two-tiered marble basin was also installed. Minor alterations occurred in the 19th and 20th century, with emergency repairs undertaken in the 1970s and 1990s (B18).
The National Trust's Survey of Stowe undertaken in 1989 contains additional details - the floor is surfaced with small pebbles; the tuffa decoration has fallen away to uncover two earlier phase of decoration one of small broken flints and another of small glass chippings (B19).
Survey, recording and excavation carried out from Summer 2003 to April 2004 by Northants Archaeology to investigate the surviving components of the water supply system. The original source of the water supply to the grotto was not established (B29).
Included in English Heritage's Buildings ar Risk Registers. In 1999 described as priority C: 'Slow decay; no solution agreed'. In 2001-2006 described as priority 3 (D): 'Slow decay; solution agreed but not yet implemented'. In 2007 described as priority E: 'Under repair…'; in 2008-9 priority D: 'Slow decay, some work done...' (B33,B37-39,B43,B45, B48).
Detailed drawings of interior decoration (B47).
Watching brief in February 2011 during works to resurface and reroute the path leading to the western side of the grotto, established the original line of the 18th century path, probably added in the 1780s. See report for detail (B55).