are present as dedicated lines operating directly from a suburb to another past the centre (for example Helsinki buses 51–54, 56–59). The line numbers for the internal lines contain two or three digits and sometimes one or two letters. Most lines are operated between 5:30 and 23:30, the most popular between 5:00 and 1:30. In daytime outside of rush hours the basic interval for buses is mostly either 10, 15, 20, 30 or 60 minutes depending on the length and the demand of the line. Nighttime lines that operate only from 23:30 to 1:30 (and sometimes early morning) are signified by the additional letter N. Recently the tradition of having designated night routes has been broken and replaced with N-variants of daytime routes. Other letters include: A: lengthened route, often to Kamppi, Elielinaukio or Rautatientori B: shortened, less direct route, often a feeder to a nearby metro station H: trams to/from Koskela and Töölö depots K: exception in route, often a lengthier route through a neighbourhood or termination somewhere different R: robot bus T: exception in route, often involving serving long cul-de-sacs or V: rush hour route (usually along a highway or busier roads) Z: faster or more direct route (usually along a highway or busier roads) Helsinki bus terminals include Kamppi (mainly used for night and rush-hour buses), Rautatientori, Elielinaukio and Hakaniemi. Larger metro stations have their own feeder bus terminals. Night bus Most daytime bus lines run between the hours of 5:30 and 23:45, with the most popular lines running until 1:30. On weekends, night buses operate between 1:30 and 4:00. During these times, there is a direct bus connection to all areas from the centre of Helsinki, while during the daytime for many of the same areas it would requird a combination of train and bus or metro and bus to get to the same places. At least 40 such night routes are part of the Helsinki bus network. As with daytime buses, the bus drivers do not sell tickets or cards onboard and they must be purchased in advance. Helsinki Central Station is the local transport hub for night buses in the city centre. Regional services The regional bus lines are today managed by HSL in similar manner to the management of the internal lines of Helsinki. The regional lines are specially designed for moving people between important points in the metropolitan area and for the