There are quite a few ways to get to Denmark. There are the typical airplane and train methods, as well as a ferry or two, which isn't surprising for a country with so much shoreline. Most everyone arrives in Denmark through Copenhagen, so I'm focusing there, though it is possible to arrive through other ports of entry.
The Copenhagen Airport, Københavns Lufthavne, is a European hub and is the main hub airport in Scandinavia. It is located in Kastrup, on the island of Amager, just to the south of downtown Copenhagen. It is quite close to the city and has frequent, direct, and fast (15 minutes) connections into the city on both metro and train. There are three terminals which are all connected, so if you end up not where you need to be, you may have a little hike, but you can walk all the way through to the one you need. The metro and trains to the city (and Malmö, Sweden) are in terminal 3. My next post will dive into getting from the airport to the city center. Read more about Arriving in Denmark