>>9870351 (pb)

Those appear to be terraced decks of a 4 - 5 level underground living unit built into the steep slope. Since the view is straight down from the drone, the eye is fooled.

Previous drops and the mil drone videos indicate that an extensive underground (4 - 5 ) level inter-connected set of separate complexes span the entire Island. The main visible feature, the blue and white small square structure house an elevator shaft.