The inspector general for the DOT reported Thursday that the department does not have a single map that accurately shows the nation's time zones and each local observance of daylight saving time.

To find the states with more than one time zone, 24/7 Tempo reviewed data from the Department of Transportation (DOT), which is responsible for overseeing time zones in the United States. Time ...

Thanks to John Ptak, who recently featured this diagram on his blog, along with a few other pre–time-zone clock charts that are equally beautiful.