The Fundy Coast (between Saint John and Alma) is for the most part wild, remote, and unpopulated. It's criss-crossed by few roads other than the Fundy Drive, making it difficult to explore deeply -- unless you happen to have brought a boat with you, which I'm guessing you didn't. The best access to this coast is at Fundy National Park, a gem of a destination that's hugely popular in summer with travelers of an outdoors bent. Families often settle in here for a week or so, filling their days with activities in and around the park such as hiking, sea kayaking, biking, and splashing around in a seaside pool.
Nearby there are also some lovely drives, plus an innovative adventure center at Cape Enrage. You can even vary your adventuring according to the weather: if a muffling fog moves in and smothers the coastline (and it might), head inland for a hike to a waterfall through lush forest. If it's a day of brilliant sunshine, on the other hand, venture along the rocky shores by foot, bike, or boat, and bring a camera.