(CNN) -- Martin Luther King Jr. used his American Express card instead of a passport to get past the Berlin Wall.
Now, 25 years after the fall of the Berlin Wall, this little known fact and thousands of previously classified documents have been released.
After an executive order issued by President Barack Obama called for the processing of classified records that are 25 years old or more, the CIA, in conjunction with the National Archives' National Declassification Center, announced it had made public more than 11,000 pages of documents detailing life and death in the shadow of the wall between 1962 and 1986.
To prevent East Germans from getting into West Berlin, the border between West and East Berlin was closed by the Soviets on August 12, 1961.
Called the "Anti-Fascist Protective Rampart" by East Germans, 155 kilometers, or 96 miles, of wall encircled West Berlin, itself a West German island in the heart of East Germany. The central part of the wall that divided West Berlin and East Berlin was 43 km, or 27 miles long.
Intelligence reports and maps included in the document release details on the construction of the wall. What began as guarded barbed wire strung along the border quickly became barbed wire with guard towers and two high concrete walls, one on the inside, one on the outside of a no man's land. This "death strip" was littered with anti-tank barriers, signal wires, beds of spikes, sand --to see footprints, and guard dogs, all under the constant surveillance of armed guards with orders to shoot on sight anyone trying to cross.
"Ich bin ein Berliner," said President John F. Kennedy when he visited the city on June 26, 1963. Many of the US government memos outline the technical aspects of a presidential trip to the city only 22 months after the Berlin Wall was erected.
Dr. Hope Harrison, who helped with the project and spoke at a symposium at the National Archives on Tuesday highlighting the document release, said massive media coverage in the West highlighted every killing. "Cross and flowers" marked death sites. She compared that to the East German approach. Coverage of the killings of people trying to escape East Berlin was "taboo," she said. But a border guard killed at the wall was "turned into a hero of socialism defending the border, streets and schools were named after them."
Hundreds of West Berliners standing on the Western banks of a narrow canal witnessed 24-year-old Gunter Litfin's death when on August 24, 1961 he become the first person killed at the Wall by guards with machine guns who shot him as he swam in the water. The killing of Peter Fechter, 18, was filmed by Western media and broadcast live as he bled to death after being shot trying to cross the border zone near Checkpoint Charlie.
That infamous checkpoint, also known as Checkpoint C, was the one Martin Luther King, Jr. managed to cross without a passport. Diplomatic cables reveal how on September 13, 1964, after speaking to large crowds in West Berlin, he used his American Express card to get past guards in order to enter East Berlin. He conducted a church service there honoring President John F. Kennedy, who had visited Berlin two years earlier. Two thousand people overflowed St. Mary's Church, where he said "There is no East, no West, no North, no South, but one great fellowship of love throughout the whole, wide world."
The diplomatic cables also highlight President Ronald Reagan's trip to Berlin, when he implored Mikhail Gorbachev, the head of the Soviet Union to "tear down this wall." It fell two years later on November 9, 1989. The CIA hasn't released classified Berlin Wall material from that year.