You can visit Botanical Garden for free. For further information and opening hours go to their website: http://botanik.snm.ku.dk/english/ Even though the gardens outside don't offer much at winter time, the greenhouses are deifinitely worth a visit. There it is possible to get a birdseye view from a canopy walk upstairs. There are also some animals you can see, if you're lucky. I saw a wren and some tropical fish.
Note that the greenhouses close at least on hour before the rest of the garden.
