Less than six feet beneath a residential neighborhood in the English seaside town of Margate lies a mysterious underground cavern. Nicknamed Shell Grotto, the subterranean passages wind for 70 feet and are adorned by millions of seashells. Who built the cavern and for what purpose remain a mystery. SUBSCRIBE: https://goo.gl/vR6Acb Follow us behind the scenes on Instagram: http://goo.gl/2KABeX Make our acquaintance on Facebook: http://goo.gl/Vn0XIZ Give us a shout on Twitter: http://goo.gl/sY1GLY Come hang with us on Vimeo: http://goo.gl/T0OzjV Visit our world directly: http://www.greatbigstory.com Great Big Story is a video network dedicated to the untold, overlooked & flat-out amazing. Humans are capable of incredible things & we're here to tell their stories. When a rocket lands in your backyard, you get in.