Chicago "L" station
O'Hare is a Chicago "L" station located at O'Hare International Airport, 17 miles (27 km) northwest of The Loop. The northwestern terminus of the Chicago Transit Authority's Blue Line, it is a subway station with two island platforms serving three tracks, situated under the parking garage for Terminals 1, 2, and 3. Trains are scheduled to depart from O'Hare every 2–7 minutes during rush-hour periods and take about 40 minutes to travel to the Loop. It is the westernmost station of the Chicago 'L' system. It is also the only station without coordinates in Chicago's grid system, the only underground terminus, and is the only terminal that does not directly connect to any CTA or Pace buses. Uniquely among "L" stations, it serves airport passengers and employees exclusively, and is not accessible by foot beyond airport terminals 1, 2, and 3. It is also one of three terminals (the others being Dempster–Skokie on the Yellow Line and Cottage Grove on the Green Line) that does not have a yard assigned to it (the yard is located at Rosemont, one stop east).