This can be done by air, land and water. Let's start with the last point - the waterway. From Norway (Norway) to Denmark (Denmark) goes the ferry. Flights are organized by several shipping companies: Color Line, DFDS Seaways, Fjord Line, Stena Line. Prices, travel time, departure and arrival ports are different. There are routes Oslo (Oslo) - Copenhagen (Koebenhavn), goes to the place 15 hours or more, Oslo - Frederikshavn (Frederikshavn) 12 hours en route, Kristiansand - Hirtshals only 3 hours on the road, etc.

By land, you can get from Norway to Denmark by bus or train, with one or two transplants. The minimum dock time between trains is 10 minutes, the journey time is from 7 to 11 hours. You can plan your route using this site. In addition, buses run from Oslo to Copenhagen, flights are mostly direct, traveling time is 9-10 hours, costs 40-46 EUR.

Air way: for about 220-400 EUR, depending on the class of the place and the airlines, you can fly from Oslo to Copenhagen.