They say that it would have taken at least two more years to defeat the German military in World War II had not some of the Nazis' secret codes fallen into the hands of the Allies.
The Germans had been using Enigma cyphers to scramble their intelligence and military communications and thought Enigma was unbreakable. But work by master codebreakers at Bletchley Park, a secret installation about 45 minutes outside London, eventually proved the Germans wrong.
At the same time, the Nazi high command was sending coded messages using a device called the Lorenz. To solve that, Bletchley Park's code breakers came up with a machine called Colossus (a reconstruction is pictured here).
CNET reporter Daniel Terdiman visited Bletchley Park as part of Road Trip 2011. And last year, as part of Road Trip 2010, he visited the U.S. National Security Agency's National Cryptologic Museum in Ft. Meade, Maryland, where many related items, including a collection of Enigmas, are on display.