Berlin Hauptbahnhof, known as Berlin Hbf, is not an airport - it is Germany's largest railway station, a glass-and-steel hub in the middle of the capital where high-speed ICE trains from across the country converge, and anyone searching for car rental at Berlin Hbf almost certainly means picking up a car near this train station rather than at any airfield. Many travelers follow exactly this pattern: arrive in Berlin by rail, then walk a short distance from the platforms to one of the rental desks operating in or around the station complex before driving onward. This suits the city well, since Berlin's commercial airport, Brandenburg (BER), sits well outside the center, while Hbf sits close to the historic core and is often the more convenient starting point for anyone whose itinerary already runs through Berlin by train.
From Berlin Hbf, the autobahn network fans out in every direction: the A2 runs west toward Hannover, the A10 ring connects to routes south and east, and further links lead toward the Baltic coast or the Polish border. Within the city itself, traffic can be dense on weekday mornings and evenings, and central Berlin operates under a low-emission zone requiring a windshield sticker, which rental cars already carry. Parking near the station is limited and metered, so most drivers collect the car and leave the immediate center fairly promptly.
Driving is on the right throughout Germany, and stretches of autobahn famously carry no blanket speed limit, though sections near cities like Berlin are commonly posted with limits for safety and congestion reasons. Roads are excellently maintained and clearly signed, fuel stations are frequent along every route leaving the capital, and there is no car-toll system anywhere in Germany, unlike several neighboring countries, which makes a rail-to-road handoff at Berlin Hbf a genuinely practical way to begin a longer German road trip without any extra tolling paperwork to arrange beforehand.