Experts say the shelters in schools and courthouses are often aging relics from the Cold War that haven't been maintained. In a real nuclear strike, taking cover in a building bearing the rusted yellow fallout-shelter symbol may not be the best option anymore. 16, 2018 photo, fallout shelter signs hang on a lamp post on East 11th Street in New York. Students bolted across the University of Hawaii campus to take cover in buildings. Parents huddled in bathtubs with their children. Drivers abandoned cars on a highway and took shelter in a tunnel. The state had set up the missile warning infrastructure after North Korea demonstrated its missiles had the range to reach the islands. People weren't sure what to do Saturday when Hawaii mistakenly sent a cellphone alert warning of an incoming ballistic missile and didn't retract it for 38 minutes. There's a threat, but it's a different type of threat today.' had nuclear warheads pointed at each other that would devastate the world. 'We're not facing what we were facing 50 years ago, when the Soviet Union and the U.S. Irwin Redlener, head of the National Center for Disaster Preparedness at Columbia University's Earth Institute. And conventional wisdom has changed about whether such a shelter system is necessary in an age when an attack is more likely to come from a weak rogue state or terrorist group rather than a superpower. Relics from the Cold War, the aging shelters that once numbered in the thousands in schools, courthouses and churches haven't been maintained.

But these days, that might not be the best option, or even an option at all.

Korean war fallout shelter sign