The British Airways ticket issued to Neville Chamberlain when he flew to meet Hitler in Munich in 1938 has sold for ?�14,000 ($23,911).
It proved the headline lot of Spink's Postal History, Autographs and Historical Documents auction in London on July 18.
Chamberlain's meeting with the Nazi leader took place on September 29 and was a last ditch attempt to halt the expansion of Germany by allowing it to annex the Sudentland - a long-contested region of Czechoslovakia.
On his return he made a speech on the steps of 10 Downing Street, announcing: "My good friends, for the second time in our history, a British prime minister has returned from Germany bringing peace with honour.
"I believe it is peace for our time. We thank you from the bottom of our hearts. Go home and get a nice quiet sleep."
As we now know his elation proved short lived. Within a year, the Nazis entered Poland and the second world war began in earnest.
The lot was presented in a manila envelope that reads: "The Prime Minister's ticket on his last visit to Munich at which an agreement with Hitler was reached. 29.9.38".
We have this signed letter from Winston Churchill, who took over from Chamberlain after his resignation in 1940.
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