My readers, please be noted that Shanghai Metro is not 24 hour in service. I had a miserable night today.
I took Metro Line #1 from Xujiahui to Metro Line #4 station at Shanghai Stadium, only to find out Metro Line #4 is already closed. The last train leaves the platform at 22:16 (inner circle) and 23:14 (outer circle).
Do pay attention to it during your next visit.
Update Their Notices March 8, 2009
Now, at the direction board inside the metro stations, they have clear marks to remind people to pay attention to the end of service time of each metro lines.