Which of these sentences is punctuated correctly?

AAlthough the concert doesn't start for over an hour; most of the fans have already arrived at the concert hall.

b.The concert doesn't start for over an hour; though, most of the fans have already arrived at the concert hall.

c.Most of the fans have already arrived at the concert hall; however, the concert doesn't start for over an hour.

d.Even though the concert doesn't start for over an hour; however, most of the fans have already arrived at the concert hall.