"the Wall, a dirty, ugly thing of breeze blocks and strands of barbed wire"

The Berlin Wall, constructed in 1961, was a concrete border separating West Berlin from the eastern sector of the city.  It was built to stop the flow of emigration from the east to the west, and was also intended to curb the rampant black market activity that threatened the economy of the German Democratic Republic (GDR, East Germany).  

Arc lights were mounted on watch towers at frequent intervals along the Wall, and a 30ft-wide strip of land on the eastern side came to be known as the ‘death strip'.  A shoot-to-kill policy for East German border guards made unauthorised attempts to cross the Wall extremely dangerous.  Between its construction and its fall in 1989, about 5,000 people successfully escaped from East Berlin, although others lost their lives in the attempt. The number of deaths is disputed but ranges from 90 upwards.

Today, many see Israel's much longer and higher West Bank Barrier as politically and morally comparable to the Berlin Wall.