Visitors may buy ticket at 5th floor and go up to 89th floor where is the observatory of great place to see the whole Taipei city. The open hours are 9am~10pm. The last ticketing and entry is 9:15pm.
How to reach Taipei 101? You may take the blue line of MRT at Taipei train station, destination to be Taipei Nangang Exhibition Center, and take off MRT at the "Taipei City Hall" station, It takes 10 minutes walking from "Taipei City Hall" station to Taipei 101.