Need tips: Going to bar harbour campground

Visiting US to meet friends and see NY/DC/Boston. Made a plan to take an RV and drive to Acadia national park. Going to be at bar harbour campground for two nights in late June. 4 of us (2M 2F)

Any tips to make this trip memorable? Hikes? Stargazing? Etc?

Anything we should be careful about? Never drive an RV before so pretty excited about it!