As gold and bitcoin climb to records, gone are the days when doomsday preppers were just fringe survivalists hoarding gold ...

Fortunately for the rest of us the National Geographic Channel's hit series Doomsday Preppers returns later ... people with expensive and elaborate bunkers in favor of those who've developed ...

The "preppers" had a variety of reasons for their doomsday stashes ... paper and bottled water to elaborate multi-million dollar bunkers. One couple in their 70s who Mills met in Texas had ...

Narrator: Doomsday prepping isn't a new idea. In the '50s and '60s, houses were built with bunkers, and shelters started popping up during the Cold War. Today's preppers have plenty of survival ...

Led by prominent Spanish architect Alfredo Muñoz, architecture firm ABIBOO Studio has worked on a long list of innovative projects from luxury celebrity homes to intergalactic cities to disaster ...