An unidentified telephone bidder bought on Thursday Checkpoint Bravo, once a major crossing point between communist East Germany and West Berlin and now a derelict slice of Cold War history.
"I am not at liberty to say who the buyer is or what their plans are," Thomas Engel from auctioneers Deutsche Grundstuecksauktionen told reporters in Berlin.
The buyer paid 45,000 euros (58,400 dollars) for the 15,000-square-metre (160,000-square-feet) site on the southwest edge of Berlin, the minimum price set by the owners, the federal government. There were no other bids.
Although less famous than Checkpoint Charlie in central Berlin, Checkpoint Bravo at Dreilinden was once one of the busiest transit points in and out of the communist German Democratic Republic (GDR).
Between World War II and the fall of the Berlin Wall in 1989, West Berlin was an enclave in the GDR, heavily garrisoned by US, British and French troops, while the Soviets held East Berlin on the other side of the wall.
While Checkpoint Charlie, where US and Soviet tanks faced off in 1961 and which is now a major tourist attraction, was for foreigners, Checkpoint Bravo was the Allied barrier where ordinary Germans passed through.
Huge numbers did so, West Germans travelling from West Berlin to the rest of West Germany through the GDR, or the lucky few East Germans given permission by the communist authorities to leave.
"There were hundreds of vehicles coming every day from both directions," remembers Harry Hartig, a former GDR border guard who helped create a small museum at the East German crossing point adjacent to Checkpoint Bravo.
"Sometimes things got very tense," the 82-year-old told AFP.
Many also risked their lives trying to escape the GDR and the clutches of the Stasi secret police, hiding in the boots of cars or by more daring means such as by hot air balloon or, in one case, hidden inside a stuffed cow.
The site up for sale on Thursday was used until 1969, before the checkpoint was moved a few kilometers (miles) away to a bigger site on a newly created stretch of motorway.
Motorists still drive through this, passing the original buildings including a distinctive former roadside restaurant, now closed and reportedly destined to become an American diner, and a statue of a bear, Berlin's mascot.
But the pre-1969 checkpoint is off the beaten track and is now in a dilapidated state with a crumbling bridge and a former cafe with smashed windows, rubbish and graffiti.
The pre-1969 path of the motorway before it was rerouted, known as the "Avus" by locals, is still visible but is steadily being reclaimed by nature, overgrown with grass, bushes and trees. Instead of cars and border guards, there are now hikers and cyclists.
It is also unclear what the buyer will be able to do with the site, since it is unlikely that he or she will get permission to construct any new buildings. It is also difficult to get to.
"I think it's strange that they are auctioning it off. I know the government needs money but I don't understand it," Hartig said. "They could have turned into another memorial of some sort."