The blue areas are the enterprise zones all controlled by the airport. Zone 1B is most of Wigmore Park apart from the northern edge. The land is flat and at the same height as the rest of the airport. Zone 1C is the long term car park and Zone 1D is due to get a second taxiway. If zone 1C and 1D became airside then the airport would gain another 40 odd stands and a new terminal thus doubling the size of the airport.
If the DART link carried on in a straight line the next stop would be Wigmore Park.