Unexplored Kent: Shell Grotto – Margate


Hidden six feet under Margate is one of Kent’s biggest mysteries: the Shell Grotto. Discovered in 1835, this Grade I listed building is made up of 4.6 million shells that adorn the walls and ceiling of the grotto. Almost all of the ceilings and walls are covered in shell mosaics, but the origin of this space still remains a mystery.

It is believed that the site was discovered in 1835. A Kent newspaper from 1938 reports that the grotto was discovered when workmen dug down and hit a large stone. This led to an extensive examination and the shell studded walls being discovered. The article described the grotto as being “one of the most curious and interesting sights that can possibly conceived, and must have been executed by torch light”. It was opened shortly after as a visitor attraction and has been privately owned ever since.

The steps from the shop lead straight down to the dimly lit and windy passageways of the grotto. After you walk through an archway the rest of the site is covered in seashells. These snaking passageways and mosaic archways are quite breathtaking. There are a wide range of designs across the site. There are a number of flora mosaics but also lots of geometric designs. At the end of the grotto is a rectangular room known as the Altar which has been the location of a number of seances.


The Shell Grotto sparks debate and discussion amongst visitors. You cannot help but wonder, who made the grotto, why and when? Some believe that it represents the journey from birth to death, ending up in the chamber of heaven. One theory is that it was created by the Romans as a religious site and is around 2000 years old. Another is that it was created by the Victorians for entertainment. Could it also have been a pirate smuggling cave? Experts believe that it would have taken multiple generations to create the site. It would have been a huge task to hew the rock, source and transport the shells and design the mosaics.

It does not matter which theory you believe in, the dedication to the shell mosaics is clear to see. I am sure that the Shell Grotto will continue to mystify visitors for years to come.

Shell Grotto is a ticketed site and costs £4.50 for adults but is free for under 16s. It is open for the summer between 10-5.

Last Updated on 9 August 2022 by Michael

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