The mayor of Germany's capital has placed a wreath at the main Berlin Wall memorial, marking the 55th anniversary of the start of construction of the Cold War structure that divided the city for nearly three decades.

Ahead of the ceremony at the Bernauer Strasse memorial, Mayor Michael Mueller also took part Saturday in a service at a chapel on the former "death strip" that divided the city.

The country was divided into capitalist West Germany and communist East Germany after World War II.

At the height of Cold War tensions, the East German regime started building the wall through Berlin on Aug. 13, 1961 and soon fortified its entire border. The wall stood until Nov. 9, 1989, and at least 138 people were killed along it during its 28 years.