There is train from Hillerød 1 hour once or twice an hour (http://lokalbanen.dk/Defa...), with an extra express train running between 6am and 5pm. There are good connections with the S-train system in Hillerød, with departures and arrivals timed with those of the S-train. If in a car, just follow route 16 Hillerødmotorvejen all the way from Copenhagen, though be mindful that route 16 breaks from the highway just east of Hillerød Frederiksværk exit.
The ferry (http://www.hundested-roer...) across the Isefjord to to Rørvig takes 20 minutes, service is scaled back considerably 06-18 outside the busy summer season. There is also a ferry from the small hamlet Sølvager south-east of the city to Kulhuse on Hornsherred (http://www.mfcolumbus.dk/) - at a mere 8 minuttes it claims to be the shortest ferry crossing in the country.
