Originally Posted by
flyinglan
it's easier to take the MRT as you are connected via underground tunnel to the airport MRT. And actually for people planning to transfer to the red or blue MRT lines, it is much easier to board at Beimen station and transfer to Blue line in Ximen or Red line in ChiangKaiShek memorial. Avoid boarding the MRT at Taipei main station, the walk is long.
I think using the Bei Men Station for the MRT is probably the best thing to do.
They also mix the platforms of the lines at both of these stations. So, once you get off the Green line, it just cross the platform to take the Red to Xiang Shan and the Blue to Ding Pu. To go to Nan Gang or Tamsui, need to change level.