Shell grotto – Be Mystified
Discovered by a little boy in 1835, this Shell Grotto has mystified scientist and the every man alike for more almost 200 years!
The Shell Grotto is an ornate subterranean passageway shell grotto in Kent. Almost all the surface area of the walls and roof is covered in mosaics created entirely of seashells, totalling about 190 sq metres of mosaic, or 4.6 million shells! It was discovered in 1835 but its age and purpose remain unknown. The Grotto is a Grade I listed building and is open to the public.
Leading to the Grotto is a passageway which snakes down until it reaches an arch, whose walls and roof is covered in shell mosaic. The arch leads to an area called the the Rotunda, which is a central circular column, and this then meets the Dome. This is a shaft rising to the surface, which is capped to allow some daylight into the structure. The base of the Dome is triangular and has an arch in the centre of each side. There is another passageway which is full of varied mosaics and leads to the Rectangular Chamber. The patterns in this room is more geometric in character, with the main subjects being sun and star shapes! there is also a focal point in this room called the Altar.
The purpose of the structure is still unknown, with theories abounding! The most widely believed theory is that it was made by a Gentleman’s club, which was the rage in the 1800’s. However other theories include, it was a prehistoric astronomical calendar, it is connected with the Knights Templar, it is connected with Freemasonry or it was even built by the Phoenicians! The fact that the patterns are Eastern in nature, Indian or Egyptian, is a very intriguing conundrum.
The most frequently used shells throughout the mosaic, that is, mussels, cockles, whelks, limpets, scallops and oysters are largely local. They could have been found in sufficient numbers from four possible bays namely Walpole Bay in Cliftonville, Pegwell Bay especially at Shellness Point, Cliffsend, near Richborough, Sandwich Bay 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 would have been collected from shores west of Southampton, where it is abundant.
In 1932, a new owner replaced the gas lighting with the cleaner electric lighting which had, over the previous ninety odd years, blackened the surface of 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. Unfortunately the gas lamps used to light the cave in Victorian times have rendered radiocarbon dating almost entirely useless in dating the age of the cave. Other methods have been used in an attempt to date the cave but so far they have proved fruitless and an investigation into the mortar used to affix the shells to the wall was only able to conclude that it was “fish based.”