Yes, big rigs are no problem for the Dauphin Island campground.
For the O P..........when you arrive, you will cross a high
bridge over the intracoastal canal. On the island, this road
comes to a 'tee'......turn left/east, and go about a mile or so,
come to a ferry landing on the left and the campground on the
right....keep going, to the campground entrance
on your right......this is a TIGHT turn, almost 180 degrees.
Swing wide left to make this right turn.