There are a handful of ultra-high-net-worth pursuits that sound tempting, but don’t really make sense. They’re typically wildly expensive and operationally inconvenient. And always difficult to ...

Personal subs have tended to be acrylic spheres with pontoons, the bulbous transparent capsules offering exceptional views, but not much interior space. Besides looking clunky, these subs typically ...

But the price tags, size and weight of the underwater craft have kept most potential buyers away from ownership. You have to be a billionaire and own a very large superyacht. Until now. U-Boat Worx’s ...