Cathedral

Cathedral is Aliwal's set-piece: a sunken amphitheater roofed at one end by a broad rock arch, with a clean sand floor that lets divers kneel in the nave while the congregation arrives. In season, ragged-tooth sharks cruise beneath the arch and stack up in the still water — the classic Aliwal photograph is a raggie silhouetted in the arch's frame. Out of season the architecture still earns the visit: soldierfish and sweepers under the roof, potato bass making inspections, rays on the sand, and the shoal's endless nudibranch inventory on the walls. Surge management is the only real skill required.

您此行的高光时刻: The arch-framed raggie silhouette; a natural amphitheater made for wide lenses

地形地貌: Sandstone amphitheater with a large natural arch and sand floor

水流: Swell-driven surge moves through the arch on bigger days; calm windows make the amphitheater easy.

危险因素: Surge through the arch and depth on the seaward side.

许可证与规定: Aliwal Shoal MPA permit required, arranged via operators.

保育: Sand-kneeling only, and never under a shark's swim line — exits must stay open for the animals.

高氧（Nitrox）: 在此值得使用——各潜点深度落在富氧空气（nitrox）能有效延长免减压时间的区间（前提是持有相应认证）。