H (S-train)

H is an S-train service in Metropolitan Copenhagen, Denmark that serves mainly the outer part of Frederikssundbanen, running partially non-stop between Ballerup and Flintholm. It is one of the six base lines of the S-train network, running every 20 minutes all days from about 5:00 until 1:00. It is the only base line in the network whose frequency is not doubled in the daytime; instead approximate 10-minute service on the outer part of the radial is provided by extending some trains on service C from Ballerup to Frederikssund. On Friday and Saturday nights there is also a 30 minutes service throughout the night.

Following stations only during rush hour.

H as a service letter was first used in 1972 for a service that was designed to be extended to Hareskovbanen, which is probably the reason why this letter was chosen. The service letter disappeared in the 1979 timetable, but was reinvented in 1989.

A limited-stop daytime line called H+ ran from 1993 to 2007, initially superseding rush-hour services Cx and Bx on the Ballerup and Farum radials:

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