Belfast International Airport is an airport 11.5 NM northwest of Belfast in Northern Ireland, and is the main airport for the city of Belfast. Until 1983, it was known as Aldergrove Airport, after the nearby village of Aldergrove in County Antrim. In 2023, over 5.9 million passengers travelled through the airport, a 23.6% increase compared with 2022. The majority of flights from Belfast International are operated by easyJet, Northern Ireland's biggest airline. It features flights to some European metropolitan and several leisure destinations.

Belfast is the capital city and principal port of Northern Ireland, standing on the banks of the River Lagan and connected to the open sea through Belfast Lough and the North Channel. It is second to Dublin as the largest city on the island of Ireland with a population in 2021 of 345,418 and a metro area population of 671,559.