Great Airports Worldwide - The International Airport
An international airport is an airport that offers customs and immigration facilities for passengers travelling between countries. International airports are typically larger than domestic airports and often feature longer runways and facilities to accommodate the heavier aircraft commonly used for international and intercontinental travel. International airports often also host domestic flights. Some, such as Frankfurt Airport in Germany are very large; others such as Fa'a'ā International Airport in Tahiti, are quite small.
do think though, as a regular user of Gatwick, thst they should get a second runway. My biggest concern with expanding either airfield, though I think they have to, is that the airspace over the UK is very congested.
I've found that I drove a car rather than walked to the major airports in the Bay Area also. Will there be a time when skipping or better yet roller skating be the preferred way to arrive at the airport.