Terminal 4 first opened in 1986 as British Airways main hub, though services continued at Terminal 3. Terminal 4 is connected to Terminals 1, 2 and 3 by Heathrow Central underground train station. Once Terminal 5 opened in March, 2008 and BA moved out, Terminal 4 became home to the SkyTeam alliance (Delta, Air France, and KLM) as well as some unaffiliated carriers. It was also impressively renovated with a new glass façade and main ticketing hall. This has resulted in reduced traffic congestion and more upscale concessions. In addition, the concourses and departure lounges have been remodeled adding two new stands to accommodate the Airbus A380 have been constructed, and a new baggage system has been installed.