air pollution. BPT also currently operates 4 bus rapid transit lines. Bus pass The BPT offered month-long bus passes until 2006. Bus enquiry services The BPT provides enquiry services via both its official website http://www.bjbus.com and a helpline: +86-10-96166. Taxi Taxi fares depend on the vehicle type: these start at CNY 13 for the first 3 kilometers, and go up by CNY2.30 per extra kilometer; the per-kilometer charge is based upon the make and model of the vehicle. After 10 pm the base fare goes up by 20%. Idling time is also factored into the total fare, which is CNY2.30 (CNY4.60 during rush hours of 07:00−09:00 and 17:00−19:00) per 5 minutes of standing or running at speeds lower than . All legal cabs will be part golden yellow or all black in color, and display their permits and paperwork on the dash board and windshield. There are also many illegal cabs known as (heiche, meaning 'Black Cabs' as in "black market" or "illegal"), which operate via a pre-negotiated fare. Taxi-like services, including Pedicabs, are also widely used. A motorized or manual bicycle is probably the most commonly seen form, although pedicabs are still available in certain parts of the city. These quaint modes of transport also employ the pre-negotiated fare system In 1999, the environmentally unsound "bread cars" (Minivans) (mianbao che, a.k.a. miandi) were decommissioned in a stringent manner. They used to charge CNY 1 per kilometre. Although it was sound, budget-wise, their poor environmental record and an increasing consciousness of the image of the capital were the factors that landed them in the dumpster. As of 2004, 1.20 RMB/km taxicabs were phased out, and as of 2006 all taxi fares were 2.00 RMB per km with the same 10 RMB starting fare for 3 km rule. The Hyundai Elantra is the common new type of taxi, along with the Volkswagen Jetta CiF. Intercity transportation Air Beijing Capital International Airport Beijing has two of the world's largest airports. The Beijing Capital International Airport (IATA: PEK) located northeast of the city center in Chaoyang District bordering Shunyi District, is the second busiest airport in the world after Atlanta's Hartsfield-Jackson International Airport. Capital Airport's Terminal 3, built during the expansion for the 2008 Olympics, is one of the largest in the world. Capital Airport is the main hub for Air China and Hainan Airlines. The Airport Expressway and Second Airport Expressway, connects