Stairs in museum

Where are the stairs in the museum, the only ones I can find are just off Carl bergsten room but it wont let me go out there. Where else can they be?

To get to the stairs exit the exhibit room from the corner opposite where you entered. You will have to turn left. walk forward and turn around to see the stairs up.

If you have not completed the memory match game on the wall. do that first.

Hope this helps