unified farecard system, such as the Optibús system that has been implemented in León, Guanajuato. Other proposed alternatives include expanding the Metro and STE trolleybus network and different forms of transportation, such as the Metrobús, which has completely replaced pesero travel along Avenida de los Insurgentes avenue, and the Tren Suburbano, which will serve areas north of the city. Unlike most other North American and European cities of similar size, it is not possible to buy a pass or farecard in Mexico City that is valid on all types of transport within the city, rather, each form of transport one boards requires an additional (but low, the Metro fare is only MXN 5 pesos) fare. Organization Pesero drivers do not receive a fixed salary but are required to meet a daily quota prescribed by the owner of the vehicle. The driver is then allowed to keep the rest of the fares of the day. This fosters fierce competition among drivers, as every passenger is seen as valuable merchandise towards meeting the quota and thus increasing the driver's personal profit. As a result, often, two or three battered down peseros race furiously against one another with complete disregard for the passengers they carry or for other vehicles. Accidents, often deadly, ensue and are fairly common. However, the lack of any real alternative keeps them in high demand throughout the city. Peseros travel fixed routes, being able to pick up or drop off passengers anywhere through the route (a major source of traffic problems and annoyance for the sudden and unexpected stops). The fees are according to distance traveled: from MXN $4.00 for a trip of up to 5 km, MXN $4.50 for a 5-to-12 km trip, and MXN $5.50 for a trip of 12 km or more. Routes usually begin in metro stations and end in outlying neighborhoods of the city or sometimes even in municipalities in Mexico State but for this purpose added to the regular fares they need to have an authorized fare by this state(with a Pyramydal Fare Scheme) for Metropolitan routes. Typically, less than $5.00 MXN routes begin in a small metro station that serves only one line, but the number rapidly increases depending on the number of metro lines going through a station. The terminal station of a metro line usually functions as a transport hub and may be served by tens of different pesero routes.