The Palm House (also known as Palmehuset) is located in central Copenhagen inside the University of Copenhagen Botanical Garden. It's a haven of tropical plants from around the world.
It's worth exploring and spending a bit of time here. And the good thing is it's free to enter.
There are two narrow iron-cast spiral staircases (one to go up and one to go down) that lead to the landing on the top of the Palm House. Come early to avoid the crowd and stroll around inside the Palm House to learn about the variety of plants here.