You can’t bring them home, but the fossilized corals that make up the Chazy Reef on Isle la Motte are definitely worth a visit. Paleontologists believe the reef was formed almost half a billion years ago, when Lake Champlain was part of the shallow Iapetus Ocean, where Zimbabwe is today. A well-marked path leads through the field to outcroppings swirled with signs of life — swirled skeletal remains of cephalopods and stromotoporoids. “Discovery Areas” are numbered and identified. The one-room museum sheds light — when it’s open.