Welcome E14
If you are not sure what airport EGLL,EGLC, etc relate to, the easiest way to find out is to go to the top of the screen and enter the airport code in the box next to where it states weather. Then go to the get weather box and in the drop down menu select decoded METAR and within a few seconds the weather details for that airport will come up but, more importantly it will also show the full airport name relating to the coded form.
Cheers.