In the UK, the largest and busiest airport is London's Heathrow; even in the world it is considered to be the third busiest and in terms of international passengers, the busiest. Because of the numbers of international passengers travelling through, the site is a place where it is possible to see people of nearly every nationality in the world. Understandably companies have not missed the profit making opportunities of such a cultural melting pot, taking advantage by building shops, car hire desks, restaurants and cafes within the terminals.

As with the majority of airports in the UK, Heathrow can trace its first use to the military. Unlike many sites however, Heathrow was being used during the First World War as an airbase that predominantly tested new developments on a variety of aircraft. At this stage the majority of the civilian aviation needs of the capital were catered for at the Croydon site. Now Croydon is a small and unused airfield, during the twenties and thirties however it was one of, if not the, major UK airport. After the Second World War however Croydon lost its position of primacy, and instead the Heathrow site took the number one position. Heathrow was heavily developed during the war years and hence, once the conflict was over, was more suited to the large planes that had been developed.

Heathrow has always been at the forefront of catering for the largest civilian planes in existence. During the fifties the Queen laid the first slabs of the new runway, built to cater for the new jet planes that would so rapidly change the aviation industry. A new runway meant that a new terminal had to be built to accommodate larger passenger numbers. At this stage however most designers believed that air travel would be reserved for the wealthy, subsequently no provisions were made for car parking as it was believed that most passengers would be chauffeured to the airport. Today however it is different, car parks at Heathrow are massive and the large number of hire car companies proves that air travel is now the pursuit of the masses.

The seventies saw further development of Heathrow, once again the runways were extended to accommodate the huge Boeing 747s that were now traversing the world. In addition however the terminal was further developed with covered runways and docking legs in order for passengers to have a stress free transition from terminal to plane. Also during this period Heathrow improved its transport links to the centre of London. A station was built that connected directly to the London Underground while additionally an overhead rail link that pulls into Paddington Station was also built.

With the introduction of the new gargantuan Airbus A380, Heathrow has once again been at the forefront of accommodating the largest passenger planes. Part of this accommodation has meant an expansion of the terminals and docking ports. As well as this however, recently the site has seen a fifth terminal being added; this terminal will purely service the aircraft flying for British Airways. Naturally this new terminal will contain all of the shops, restaurants, and car hire desks that come as standard in the modern airport.

Current estimates place the average annual passenger numbers at around the seventy million mark. This is approximately double the number of any other airport in the UK. Understandably, the airports position of primacy is somewhat assured. However, the airport executives will have to remain up to date on aircraft developments in order to cater for the largest and most modern aircraft.