The Battle of the Seelow Heights was part of the Berlin Strategic Offensive Operation. A pitched battle, it was one of the last assaults on large entrenched defensive positions of the Second World War. It was fought over three days, from 16 to 19 April 1945. Close to 1,000,000 Soviet soldiers of the 1st Belorussian Front, commanded by Marshal Georgy Zhukov, attacked the position known as the "Gates of Berlin". They were opposed by about 110,000 soldiers of the German 9th Army, commanded by General Theodor Busse, as part of the Army Group Vistula.