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.

Buildings, operations and management have become increasingly sophisticated since the mid 20th century, when international airports began to provide infrastructure for international civilian flights. Detailed technical standards have been developed to ensure safety and common coding systems implemented to provide global consistency. The physical structures that serve millions of individual passengers and flights are among the most complex and interconnected in the world. By the second decade of the 21st century, there were over 1,200 international airports and almost two billion international passengers along with 50 million metric tonnes of cargo were passing through them annually.

In August 1919, Hounslow Heath Aerodrome, in London, England was the first airport to operate scheduled international commercial services. It was closed and supplanted by Croydon Airport in March 1920. In the United States, Douglas Municipal Airport in Arizona became the first international airport of the Americas in 1928.

The precursors to international airports were airfields or aerodromes. In the early days of international flights, there was limited infrastructure, "although if engine problems arose there were plenty of places where aircraft could land". Four-engined land planes being unavailable for over-water operations to international destinations, thus/therefore flying boats became part of the solution. At the far end of the longest international route (which became the Kangaroo Route), on-water landing areas were found in places such as Surabaya and in the open sea off Kupang. In Sydney, Rose Bay, New South Wales, was chosen as the airport landing area.

...
Wikipedia