The C and D midfield concourses were the first new gates to open at IAD since its 1962 opening. Up to this point, most airliners were parked at stands with passengers transported to/from the main terminal using the iconic Mobile Lounges. The C and D concourses, completed in 1983, were originally designed as a temporary base for United Airlines, which began hub operations here in 1985. American Airlines also created a focus city operation at IAD for principally its longer-haul transon routes at C and D as well. The aging concourse was given a face lift in 2006 which included light fixture upgrades, new paint finishes, new ceiling grids and tiles, heating and air conditioning replacement, and complete restroom renovations. Nevertheless, compared to A/B and the Eero Saarinen terminal, Concourse C/D is an embarrassment and extremely outdated. It will likely be 35 years old before this “temporary” concourse is replaced. This terminal also has a dedicated Federal Inspection Station ("FIS") for arriving United as up until the acquisition of Continental, IAD was United’s main hub on the East Coast, particular for International Service. In fact, it is from this concorse that the first Boeing 777 entered service back in 1995 between London Heathrow and Dulles. The antiquated Mobile Lounges still connect this far afield mid-field concourse with the main Eero Saarinen designed main terminal. A new and permanent C/D terminal (has been long planned as part of the D2 Dulles Development Project. It is to include a three-level structure with 44 airline gates and similar amenities to Concourse A/B which was completed in 1998. Like Concourse A/B, the new C/D would be connected to the main terminal via underground trains, finally relinquishing the role of the Mobile Lounges to near zero.