The battle in Berlin was an end phase of the Battle of Berlin. While the Battle of Berlin encompassed the attack by three Soviet fronts (army groups) to capture not only Berlin but the territory of Germany east of the River Elbe still under German control, the battle in Berlin details the fighting and German capitulation that took place within the city. The outcome of the battle to capture the capital of Nazi Germany was decided during the initial phases of the Battle of Berlin that took place outside the city. As the Soviets invested Berlin and the German forces placed to stop them were destroyed or forced back, the city's fate was sealed. Nevertheless, there was heavy fighting within the city as the Red Army fought its way, street by street, into the centre. On 23 April 1945, the first Soviet ground forces started to penetrate the outer suburbs of Berlin. By 27 April, Berlin was completely cut off from the outside world. The battle in the city continued until 2 May 1945. On that date, the commander of the Berlin Defence Area, General Helmuth Weidling, surrendered to Lieutenant-General Vasily Chuikov, commander of the Soviet 8th Guards Army, a component of Marshal Georgiy Zhukov's 1st Belorussian Front. Battle of the Oder–Neisse The sector in which most of the fighting in the overall battle took place was the Seelow Heights, the last major defensive line outside Berlin. The Battle of the Seelow Heights was one of the last pitched battles of World War II. It was fought over four days, from 16 April until 19 April 1945. Close to one million Soviet soldiers and more than 20,000 tanks and artillery pieces were in action to break through the "Gates to Berlin" which was defended by about 100,000 German soldiers and 1,200 tanks and guns. On 19 April, the fourth day, the 1st Belorussian Front broke through the final line of the Seelow Heights and nothing but broken German formations lay between them and Berlin. Marshal Ivan Konev's 1st Ukrainian Front, having captured Forst the day before, was fanning out into open country.