How do you get in the museum in batman arkham city?

Answer 1

If you haven't beaten the game yet, just keep playing and it will open soon enough. If you have, your game could be glitched or if you go around the right side of the museum you will see a door, walk up to it and if there are thugs answering the door then don't bother you haven't got far enough in the game' if they are cops then they will let you in and you should get it from there. Hope this helped.

Answer 2

If you mean the first time, you have to open the shutter using the electrical charge gadget, and then do a running slide under it.

If you mean the third time, you enter the same way you left the second time, gliding into the back, or dropping onto the ice and grappling up.