Shell Grotto, Margate

The Shell Grotto consists of a winding subterranean passageway, about high and in length, terminating in a rectangular room, referred to as the "altar chamber" and measuring approximately . The grotto is entirely underground. Steps at the upper end lead into a passage about wide, roughly hewn out of the chalk, which winds down in serpentine fashion until it reaches an arch, the walls and roof of which here onward are covered in with shell mosaic. The arch leads to what is known as the "rotunda", a central circular column, meeting at the farther side at the dome — a shaft rising to the surface, capped to allow some daylight into the structure. The sub-base of the dome is triangular, equilateral, and with an arch in the centre of each side. The two arches in the sides are those leading from the rotunda, whilst the arch in the base leads into the "serpentine passage". This passage, with its curving walls and over-arching vaults, is rich in mosaics of varied design. At the end of the serpentine passage, a further arch leads into the rectangular chamber. Here the decoration takes on a more formal and geometric character, but still finely drawn and executed. The subjects are chiefly star and sun shapes. The focal point, the "altar", is the curved niche, which faces the gothic-style entrance arch. The most frequently used shells throughout the mosaic — mussels, cockles, whelks, limpets, scallops, and oysters — are largely local. They could have been found in sufficient numbers from four possible bays: Walpole Bay in Cliftonville; Pegwell Bay especially at Shellness Point, Cliffsend, near Richborough; Sandwich Bay, Sandwich; and Shellness on the Isle of Sheppey. The majority of the mosaic is formed from the flat winkle, which is used to create the background infill between the designs. However, this shell is found only rarely locally, so could have been collected from shores west of Southampton, where it is abundant. == History ==

Origins The origin and purpose of the structure are unknown. A member of the Kent Archaeological Society analyzed the grotto and concluded in 2006 that it was likely a mediaeval denehole, a small chalk mine, reworked and decorated in the 17th or 18th century. The decoration may have been created or added to in the early 19th century. People have come up with a variety of speculations and hypotheses for the age and purpose of the grotto, such as: it was an 18th or 19th-century rich man's folly; In the late 1940s, a writer, who was also interested in the Baconian theory of Shakespeare authorship, published a book about his theory of Phoenician origins for the shell grotto. In 1952, a member of the Canadian Geographical Society claimed similarities between the shell decorations and Bronze Age art from the Minoan civilization. Discovery There are conflicting accounts of the grotto's discovery, although most agree on a date of 1835. The earliest reference to the discovery appears in an 1838 article in a predecessor of the Kentish Mercury: It has remained in private ownership ever since. Tourist attraction and historic site In 1932, a new owner took over the grotto, and soon afterwards substituted electric lighting for the gas lighting that, over the decades, had blackened the once-colourful shells. Cleaning trials show that in the majority of the grotto, the shells have lost their colour under the dirt and are white. One of the walls was damaged by bombing during World War II and later reconstructed. In 1981, new owners purchased the grotto and adjacent houses. In 1992, they said they averaged about 17,000 visitors during the tourist season between Easter and October, down from 30,000 in the early 1980s. The structure has suffered the effects of water penetration. By 1999, it needed significant reinforcement and drainage improvements. The Friends of the Shell Grotto was formed in 2008 and is a not-for-profit trust established to promote, conserve, and preserve the grotto as a unique historical monument. It was removed from the Heritage at Risk Register in 2012 after a five-year conservation programme, carried out in partnership with Historic England. A scheme to sponsor replacement mosaic panels, the Roundel Project, was established in 2012. Additional restoration work was undertaken in 2025. The owner has participated in initiatives to bring more tourism and economic activity to Margate. Other local tourist attractions include the Margate Museum and Crab Museum. == Cultural depictions ==

Novels that feature the grotto include The Realm of Shells (2006), by Sonia Overall, and ''Elijah's Mermaid'' (2012), by Essie Fox. Rosa Rankin-Gee's 2021 novel Dreamland also contains a description of the shell grotto. ==References==