It is the only major London airport with significant runway capacity and offers a European route network which is unrivalled in the UK, providing London with more visitors from Europe than any other airport.

London Stansted Airport (STN) is considered a large and significant airport, serving as the UK's fourth busiest international hub, but its design makes it feel much more compact than Heathrow. It consists of a single, massive passenger terminal designed by architect Norman Foster, which is highly efficient because all departures and arrivals are processed in one building. However, the airport’s "size" becomes apparent once you pass security; most passengers must take an automated track transit system (monorail) to reach the satellite piers where the gates are located. In 2026, Stansted is the primary base for low-cost carriers like Ryanair, meaning it handles a massive volume of short-haul European flights—often over 25 million passengers a year. While it doesn't have the multiple terminals or the sheer physical sprawl of Heathrow, the "walking distances" within the satellite buildings can be long. For travelers, Stansted is "big" enough to offer world-class retail and dining but "small" enough to be navigated in about 15–20 minutes once you are familiar with the monorail system.