The days when Berlin was a great city were gone. The city was reduced to rioting, scavenging, and looting. Citizens were starving, dehydrating, and dying; all because of Hitler... And still, Hitler forced them to fight for Germany. It was clear they have lost the war, but the insane Hitler pressed on.
For the German army, it would be their last stand. They could either defend Berlin to the death, or die anyways. They had little to lose... they've already lost their country and pride. Land mines, traps, and fortifications were set up all over the city. Streets were blocked off, and every defensive point for the Germans was taken advantage of. The Allies had reduced the city to rubble as the American and British air planes bombed the city to smithereens. Many of the citizens called underground their home. On the ground, troops fired constantly. Russian artillery shells pounded Germany to bits.
The Russians finally broke into the city, and headed for the center. Just at that moment, Germans (old, young, and disabled), fought for the last time. They came from every imaginable defense, and poured artillery on the Russians. But the Russians pressed on. On April 25, 1945, Berlin was split in two as the two Russian armies merged at the center of the city and took the government offices. The city could take no more. It surrendered on May 2, 1945.
The Russians reduced the city to rubble and death. Berlin was in agony, and was still dying even after the death blow by the Russians. General Eisenhower was later criticized for letting the Russians take Berlin. Although the Battle of Berlin was over, the war wasn't.