You see them in every city across the world, but what is a manhole exactly? Manholes have been around for decades and usually go unnoticed to the average city resident. With around 12 million sewer or ...

Every so often in New York City, a disk of cast iron weighing up to 300 pounds will burst out of the street and fly as high as several stories before clattering back to the blacktop. Flames, smoke or ...

: Why are manholes often an inch or two below the road surface? They create an awful jolt when you drive over them. Amy in short: They shouldn't be, and the fact that they are is perhaps a failure of ...