UK Departure Airports
Flights to Sydney from the United Kingom depart almost exclusively from London Heathrow owing to the size of aircraft needed for such a long journey and the subsequent requirement of a suitably long runway and also enough passengers to justify the journey.
It is possible to get flights to Sydney from Manchester too, though not as many as from Heathrow, and if other regional airports are preferred then it will have to be a shuttle flight and a change at Heathrow to pick up the main flight.
London Heathrow is the country's busiest airport, with around 67 million people travelling through it annually, showing how important it is for the nation, and the sheer weight of traffic that clearly flies through it. As a comparison, Manchester Airport, the other place where flights to Sydney can be picked up, has around 23 million passengers each year, this being the second busiest airport in the UK along with London Gatwick, where a similar number of people travel.
An interesting aspect of travel to Sydney is the route taken, which can have an impact on the amount of luggage allowed, an important point for many. Routes that go via the USA have a greater baggage allowance than those that go via the Far East, so Air Canada and Virgin Atlantic would have an allowance in the region of 64 kilos total whilst a carrier like Singapore Airlines or one of the other Eastern airlines would be in the region of 23 kilos.