 Line 2 opened on September 20, 1984; Line 13 opened on January 28, 2003; and Line 4 opened on September 28, 2009.With the addition of Line 13 and Line 4, Xizhimen Station became the second 3-way transfer station (the first was Dongzhimen Station, being the intersection of Line 2, Line 13, and Airport Express).With a peak daily ridership of over 770,000 passengers, Xizhimen Station is also one of the most crowded stations of the whole Beijing Subway system.