An acoustic structure, including a pipe (110-1 to 110-3; 210-1 to 210-3; 310-1, 310-3, 310-6; 410-1 to 410-3; 510-1 to 510-2) having a plurality of cavities (120-1 to 120-4, 120-5 to 120-7, 120-8 to 120-9; 220-1 to 220-6, 220-7 to 220-10, 220-11 to 220-12; 320-1 to 320-2, 320-4 to 320-7, 320-10 to 320-12; 420-1 to 420-4, 420-5 to 420-7, 420-8 to 420-9; 520-1 to 520-4, 520-5 to 520-6) that are partitioned by a partition (130; 230), each of the plurality of cavities extending in a first direction that is a longitudinal direction of the pipe, wherein the pipe has at least one opening (140-1 to 140-4, 140-5 to 140-7, 140-8 to 140-9; 240-1, 240-2, 240-3; 340-1 to 340-2, 340-4 to 340-7, 340-10 to 340-12; 440-1 to 440-4, 440-5 to 440-7, 440-8 to 440-9; 540-1 to 540-4, 540-5 to 540-6) which permits the plurality of cavities to communicate with an exterior of the pipe, a position of each of the at least one opening in the first direction being a first position.