Hell is a Place on Earth
Office workers on Queen Victoria Street in Central London are often perplexed to find groups of Japanese tourists crouched down on the pavement peering into a small hole in the ground, screaming and running away. One of Japan's major tourist guides to London lists the unusual sightseeing spot, right after the entry on nearby St Paul's Cathedral.
Although the concept of Hell is not central to Shinto and other Japanese belief systems, there is an idea of an Underworld full of flickering green lights, where unsettled souls go to contemplate their mistakes on Earth. The hole in the pavement is actually a small electrical vent, right above a 'covalent signalling bolt' belonging to London Underground - hence all the flashing green lights which scare those tourists!