Bar Island is an extremely popular hike in Bar Harbor, Maine, near Acadia National Park. This hike is crowded because it is only available at low tide when you are able to approach the island on foot. But beware! If you dawdle too long, you’ll be stuck on the island for 9 hours, or need an expensive water taxi to pick you up. Bar Island Trail was one of our favorite hikes because there were lots of fun things to see, and it was an adventure hiking out to the island.