How many days needed in CPH?

Depending on your time of arrival you could do this on the first day:

• Stroget
• hojbro plads
• grabrodretorv, nytorv The distances are short and as long as you don't sit down you should be able to stay awake.

Second day:

• islands brygge
• vor Frelsers kirke
• Christiania ( maybe by bike tour)
• Canal cruise
• Nyhavn (Lunch) - you can swap the last two if that suits you better for time
• the glyptotek
• Tivoli (In the evening)

Third day:

• amager strandpark
• kastrup sea baths
• little mermaid

I think you can do the third day before you go to the ferry to Oslo (assuming yo will sail to Oslo on the night cruise)

Add day trips in between. Since most of this does not require booking you can go with the weather.

Good points by I.P. I would like to add that you should have a look at the guided tours of Christiania by the local inhabitamts http://rundvisergruppen.dk/indexENG.htm
Regarding day trips look at www.rejseplanen.dk for all public transport. Note that both Ribe and Ærø are really too far to be suitable as day trips.

Thanks very much for replying.

l.p.enersen, in order to get as much time in each country as possible, we are going to fly to Oslo. I understand that the ferry takes 16.5 hours!

Morten, thanks for the suggestion about using a local guide for Christiania. I didn't know that was an option.
Re: Ribe and Aero, those would be overnights, but I am not sure we will have time.

I understand that the ferry takes 16.5 hours!

That's true! But you board around 16:00 and arrive in Oslo around 09:00, so you miss an evening and a night in Copenhagen and that's all. However it's your vacation, so you do what rocks your boat (pun intended)

We have walked directly from the ship in Oslo to the tourist bus, which will drive you around Oslo and show you all the sites and end just behind the Town Hall at a time when your hotel will be ready to receive you.

I agree with I.P. I took the ferry a couple of months ago. You leave late afternoon in the afternoon and arrive early in the morning.

The view from the boat the last couple of hours before arriving in Oslo was amazing.

The cost of the cruise including private cabin was less than a hotel room in either Copenhagen or Oslo and that's not even including the airfare.

The ferry sounds like a great option. Thanks for the information :)

I would like to add som destinations if you wanted to see Helsingor also. Helsingor got the old "Hamlet"-castle, where you easy spend a day discovering. Check out http://kongeligeslotte.dk/en/palaces-and-gardens/kronborg-castle.html

Then between Helingor and Copenhagen you've got the world oldest tivoli. Dyrehavsbakken. I took some pictures from this place when I visited it a couple of years ago see http://www.bikedenmark.nu/
Easisest way to get there is by using the s-train or oresundstog and get of by the Klampenborg station. And remember. you are not able to check all of Copenhagen in one week. I've been living and working in Denmark for a couple of years and still got thousand of places to discover.
I wish you a nice visit.