Line 9 was the 8th metro line to be built in the network, built between 1985 and 1988. (
Line 8 started operations in 1994.) It is identified by the color dark brown, and runs from East to West in an almost straight fashion. It was built in order to support Line 1, providing a redistribution alternative for east–west commuters. It starts in the multi-line transfer station
Pantitlán and ends at the western neighborhood of
Tacubaya, both stations also served by
Line 1. As a comparison, the section between Pantitlán and Tacubaya is served by 19 stations in Line 1, whereas Line 9 has only 12, which would translate in a faster alternative. Line 9 is built in its easternmost section above the Rio Churubusco and
Rio de la Piedad Avenues. Then it reaches an underground route near the
Magdalena Mixiuhca Complex and it continues under the Eje 3 Sur until reaching the Tacubaya zone, where the last station is built under Jalisco avenue. As part of the first expansion plans in the 1980s the line is expected to turn west after Jalisco Avenue to reach
Observatorio Station. ==History==