A Flooded Quarry, a Mysterious Millionaire and the Dream of a new Atlantis
12th December 2025
The Guardian, a Voice of the Crust.
own an easy-to-miss turnoff on the A48 just outside Chepstow on the Welsh border, the gentle rumble of trucks, cranes and people at work mixes with birdsong in what is an otherwise peaceful rural setting. It is a crisp and sunny winter morning when I visit and, at first glance, the site appears to be little more than prefab containers and a car park. Yet, behind the scenes a group of men and women with expertise in diving, marine biology, technology, finance, construction and manufacturing are building something extraordinary. They have come together with a single mission statement: to make humans aquatic.
Their project is called Deep (not The Deep) and the site was chosen after a global search for the perfect location to build and test underwater accommodation, which the project founders say will enable them to establish a “permanent human presence” under the sea from 2027.
So far, so crazy sounding. Yet Deep is funded by a single anonymous private investor with deep pockets who wants to put hundreds of millions of pounds (if not more) into a project that will “increase understanding of the ocean and its critical role for humanity”, according to a Deep spokesperson. Its leadership team remains tight-lipped not only about the amount (they will only say it is substantially more than the £100m being invested into the Deep campus near Chepstow), but also about the investor’s identity. Whoever is behind it, the size of the investment means that an ambitious-sounding idea appears to be swiftly becoming a reality.