Word to the wise: Remember to stamp your ticket at the yellow boxes at stations, otherwise you might be hit with a fine by inspectors.
Although owned by different companies, tickets for the Metro and S-trains (and the city's bus network) are interchangeable. Like the Metro, the S-trains put other European transport systems to shame - not only clean and efficient, but also with free Wi-Fi.
A journey out of the city centre will probably start from one of its two hubs, Central Station or Nørreport Station. Although you'll rarely wait more than 10 minutes for a train during the day, be aware that frequency can drop to every hour during weekend nights.
Ticket pricing is determined by zone - the city centre lies within zones one and two. If you're planning to explore further afield, look into a City Pass which allows unlimited travel on S-train, Metro, and the bus network over a certain time period.
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