Billund Airport had its beginning in 1961 when the son of the founder of the Lego Group, Godtfred Kirk Christiansen, established a private 800-meter long runway and hangar north of his factory in Billund. With Christiansen as a key driver, more of the neighbouring municipalities were included in the group of owners, and it was planned that the airport should be expanded to a regular public airport.
Parking capacity at Copenhagen Airport was greatly expanded in 2015 with the construction of a new lot as one of the first phases in an ambitious airport expansion plan scheduled to roll out in the coming decades. There are several lots: those near the terminals are very expensive, while the further-flung ones are cheaper (but have free shuttle bus service to the terminals). 

Copenhagen is not only the main airport for the densely-populated Øresund region, but also the main air transportation hub for Scandinavia, the main hub for the joint Danish-Swedish-Norwegian carrier SAS Group, and one of Europe's major hubs. There is a large number of intercontinental connections to Copenhagen, as well as a dense network of short-haul connections from Copenhagen to destinations throughout all of Europe, especially the Nordic countries.
The cockpit, including the stickers on the sides and the canopy, is identical to that of the first jet, as is the front of the aircraft. As previously noted, however, the wing configuration is different, as is the tail design which features twin tail fins and a pair of fuselage-mounted tailplanes. The red 4 x 1 x 3 tail fins, which have appeared in a total of seven sets including this one, are angled outwards similar to the arrangement on an F/A-18 Hornet. Overall, it’s another sleek design but once again the smooth lines are somewhat spoiled by the prominent canopy.
The last of the three aircraft is a modern biplane. This incorporates a number of rare orange elements including right and left 8 x 3 wedge plates which make up the wings and have only previously appeared in three sets, a 3 x 4 wedge brick only previously found in two sets, and a 3 x 6 round half plate with a 1 x 2 cutout which has only previous appeared in a single set in this colour and which forms the tailplanes. Similar to the two jets the tail fin is stickered rather than printed, as are the pair of 1 x 4 x 1 panels making up the sides of the cockpit. Unlike the jets, however, the instrument panel is stickered, which seems odd as there are existing printed 1 x 2 light bluish grey tiles which could have done an acceptable job. There are also a pair of stickers which represent the engine exhausts and which are applied to a couple of modified 2 x 4 x 1 1/3 bricks with curved top which sit just behind the propeller; applying these neatly to the curved surface takes a steady hand, and that’s also the case for the pair of checkerboard stickers which are stuck onto the propeller cowl. As if stickered exhausts weren’t enough, there are also a couple of light bluish grey exhaust pipes with Technic pin which emerge from the propeller cowl and run along either side of the fuselage. They’re entirely superfluous given the presence of the stickered exhausts but they still look cool regardless!
City has had many games since it was released. One in particular, The Robot Chronicles, was a cross-over game which saw the City, Racers, and Agents 2.0 all together in Lego City, where the player controlled and unlocked vehicles in each theme to play through a campaign. This campaign/game was also tied into a My LEGO Network The Robot Chronicles campaign- playing the game earned rewards in MLN which could be used in that campaign to eventually get the Key to LEGO City.
SAS is a member of Star Alliance, meaning that many of their flights are code-shared or can be interlined with local Star Alliance partners. Therefore, you can take advantage of a one-ticket flight to, from, or via Copenhagen even if your origin or destination is not directly served by SAS. Norwegian is not a member of any alliance, but they offer connecting flights from Copenhagen to their European destinations on one ticket with an intercontinental flight.
The remainder of the build is the control tower and terminal building. First there is a metal detector screener leading to the waiting/secure area of the airport, which seems taller than it needs to be for the minifigures. I think the same effect could have been made with half the height, except that would not allow for an impressive height for the overall tower. However it does seem to be similar to many modern airports with the high ceilings. This area also seems to be someplace to check luggage as evidenced by the rather nifty conveyor belt that comes in a full part. The moving parts of the set include a revolving door (a very tall one, for the first floor) that leads from the secure area of the airport out to the tarmac, and of course the conveyor belt.