Germany is marking the 75th anniversary of the most famous plot to kill Adolf Hitler.

The event will pay tribute to the conspirators who were executed for trying to assassinate the Nazi dictator.

Chancellor Angela Merkel is attending the annual swearing-in ceremony for some 400 troops before addressing a memorial being held in the courtyard of the building where plot leader Col Claus von Stauffenberg was executed.

CORRECTION Germany Resistance AnniversaryA photo of Claus Schenk Graf von Stauffenberg, left, and Albrecht Ritter Merz von Quirnheim is displayed a the exhibition at the German Resistance Memorial Centre (Markus Schreiber/AP)

Col von Stauffenberg tried to kill Hitler with a briefcase bomb on July 20, 1944, but a table blocked the full force of the blast and Hitler survived.

Col von Stauffenberg and his fellow plotters were executed within hours.

Painted as traitors by the Nazis, they are now seen by many in Germany as heroes.