Scandlines is currently working on changing their ferries running between Helsingør in Denmark and Helsingborg in Sweden into electric ferries which will benefit the environment considerably.
Read more about their effort here >>

Stay at eco-labeled hotels on both sides of the Sound
The Swedish tourists can stay at one of many eco-labeled hotels in the area such as Marienlyst Strandhotel or Konventum. A bit outside of town there is Comwell Borupgaard and Havreholm Slot. Camping opportunities are also offered at Helsingør Camping 'Grønnehave'.

On the Swedish side of the Sound there are also Green Key alternatives to choose from in Helsingborg such as Elite Hotel Marina Plaza, Radisson Blu Metropol Hotel, Good Morning+ Helsingborg and Elite Hotel Mollberg.