Copenhagen airport is the largest airport in Denmark, but there are also two smaller airports in the area, Aarhus (Tirstrup) and Billund.
Copenhagen Airport is the largest airport in Denmark, with hundreds of flights a day from around the world. To reach Aarhus from this airport you need to either take a connecting flight into Aarhus airport or take a train.
The main train station in Aarhus is in the centre of the city. There is a direct service from Copenhagen to Aarhus which takes about 3 hours, with at least one train an hour. Schedule your journey here.
Current timetables for ferries to Zealand (Aarhus-Odden/Aarhus-Kalundborg):
Mols-Linien (in danish only)