Economy of London project is construction of 42 km (26 mi) of new tunnels connecting stations in central London including a branch to Canary Wharf in east London. It is Europe's biggest construction project with a £15 billion projected cost. An additional line, Crossrail 2, has been proposed. London is served by six international airports which are the world's busiest city airport system by passenger traffic. These are Heathrow, Gatwick, Stansted, Luton, London City, and Southend. There are a number of proposals for expanding airport capacity for London including expansion of London Heathrow Airport and expansion of Gatwick Airport. The principal argument in
London Southend Airport aircraft based at Southend to four. In February 2018, Air Malta announced that it would begin flights to Cagliari, Catania and Malta. In March 2018, it was announced that Loganair would begin operations from the airport to Carlisle Lake District Airport. In June 2018, Ryanair announced that it would open a base at Southend, basing three aircraft there operating 55 flights per week to 13 destinations. The following airlines operate regular scheduled and charter flights at London Southend Airport: Routes accounting for more than 2.5% of passenger traffic, or 27,397 passengers, are shown below: Since 2011, the airport has its