What is significant about transfer airports?

Transfer airports are significant primarily because they have a high percentage of enplaned passengers transferring to other flights. This characteristic is essential as it indicates the airport's role in the larger air transportation network, allowing connections between different flight routes. Such airports often serve as hubs for major airlines, facilitating the movement of passengers who need to change planes to reach their final destinations.

These airports typically experience increased traffic not just from local travelers but also from those connecting between various flights. The higher number of transfers can lead to more efficient scheduling and operations for airlines, as well as enhanced connectivity for passengers traveling long distances. This role is crucial for the overall efficiency and functionality of air travel, supporting both domestic and international routes.