The Berliner Verkehrsbetriebe and the Deutsche Bahn manage several dense urban public transport systems.
Berlin has two commercial airports. Tegel Airport (TXL), which lies within the city limits, and Sch�nefeld Airport (SXF), which is situated just outside Berlin's south-eastern border in the state of Brandenburg. Both airports together handled 22.3 million passengers in 2010. In 2011, 88 airlines serve 164 destinations in 54 countries from Berlin. Tegel Airport is the European hub of Air Berlin, whereas Sch�nefeld services mainly low-cost airline travel.
Berlin's airport authority planned to transfer all of Berlin's air traffic in 2012 to a newly built airport at Sch�nefeld, to be renamed Berlin Brandenburg Airport (BER). Due to technical difficulties, the opening has been delayed till 27 October 2013.
Berlin is well known for its highly developed bike (cycle) lane system. It is estimated that Berlin has 710 bicycles per 1000 residents. Around 500,000 daily bike riders accounted for 13% of total traffic in 2009. Riders have access to 620 km (390 mi) of bike paths including approx. 150 km (93 mi) mandatory bicycle paths, 190 km (120 mi) off-road bicycle routes, 60 km (37 mi) of bike lanes on the roads, 70 km (43 mi) of shared bus lanes which are also open to bicyclists, 100 km (62 mi) of combined pedestrian/bike paths and 50 km (31 mi) of marked bike lanes on the sidewalks.
Berlin's energy is mainly supplied by the Swedish firm Vattenfall, which relies more heavily than other electricity producers on lignite as an energy source. Because burning lignite produces harmful emissions, Vattenfall has announced its commitment to transitioning to cleaner sources, such as renewable energy. In the former West Berlin, electricity was supplied chiefly by thermal power stations. To facilitate buffering during load peaks, accumulators were installed during the 1980s at some of these power stations. These were connected by static
