Text: The island's most popular excursion prettiest by boat from Marina Grande, but also possible by road northwest of Anacapri is to the celebrated marine cave, the Blue Grotto (Grotta Azzurra), most effective (and crowded) at noon.
Entailment: The excursion to the marine cave is possible by both road and boat and is prettiest by boat.
Contradiction: The least popular excusion to the celebrated marine cave is prettiest by foot on the road northeast of Anacapri.