An underground grotto in the South of England has been named as the country's 'most mysterious place' as its origins are shrouded in secrecy - and it makes a great day out12:15, 28 May 2026One of England's most "mysterious" places is an underground grotto you can explore. The UK is packed with incredible places to discover, from breathtaking landscapes like the Lake District to ancient castles and captivating caves. And while we can usually work out how most of them came to exist, whether man-made or natural, there remain a handful of places that continue to baffle us.‌If you fancy visiting "the most mysterious place in England" - a spot so puzzling that even experts can't reach a consensus on how it was created or what it was used for - then you need only travel to the South of England, as it's located in Kent. A woman recently shared a video of the magical spot on social media, and now people are clamouring to see it for themselves.‌The remarkable location is the Shell Grotto, also known as the Shell Temple, situated on Grotto Hill in Cliftonville, Margate. The grotto is an elaborate underground network made up of a passageway and a main chamber, with almost every inch of the walls adorned in mosaics crafted entirely from seashells.‌The shells span an area of around 2,000 square feet, with approximately 4.6 million shells incorporated into the design. Not only is the grotto a breathtaking sight, but it also holds an enormous mystery, as nobody knows its age, its purpose, or even who built it.In a video posted on TikTok by a woman named Ani, she said: "I think I just found the most mysterious place in England."Content cannot be displayed without consent‌Those commenting on Ani's video were equally captivated by the site. Some expressed their desire to visit themselves, while others who'd already been to the grotto were quick to echo Ani's view that it was "mysterious".One person said: "I've been to the Shell Grotto a couple of times, it's stunning."Another added: "Can confirm, this is a really cool place!"‌A third wrote: "Wow, that is phenomenal."According to the Shell Grotto website, the site was discovered "by chance" in 1835, and since that moment, experts have been attempting to determine its original purpose. Some believe it served as an ancient temple, while others remain convinced it was a gathering place for a secret society.The Grotto has remained in private ownership since its discovery, and continues to be so today. However, it received Grade 1 listed status in 1973, meaning Historic England now oversees its conservation. There's also a Friends of the Grotto organisation, established in 2008, which helps to further protect and preserve the site.Article continues belowAs the grotto remains privately owned, it isn't permanently accessible to the public, nor is entry free. The grotto opens Wednesday through Sunday from 10am until 5pm, with tickets priced at £6 for adults and £4 for children, while under-4s enter free of charge.Throughout the summer holidays, from 22nd July to 6th September, the Grotto opens daily.For more information, visit the Shell Grotto website.