The folks over at the UK’s main air traffic service NATS have provided a superb example of the daily complexity and volumes of air traffic across the UK and Europe.
The visualization provides for
a unique view of the holding stacks over London and how they are a fundamental part of the Heathrow operation, providing the constant flow of traffic that makes it the world’s busiest dual runway airport with 1,350 movements a day.
More at NATS blog.