Mikomoto Island

Mikomoto is a lighthouse rock nine kilometers off Shimoda where the Kuroshio delivers the goods: from early summer into autumn, scalloped hammerheads school in the flow, and the standard dive is a brisk drift along the ridges scanning up-current until the silhouettes assemble. Schools range from polite handfuls to processions that take minutes to pass. Amberjack and rays ride the same conveyor, and the rocks themselves wear a hardy crop of soft coral. This is Izu's serious dive, with real current, real blue-water discipline, and rewards sized to match; local shops vet experience levels for good reason.

その瞬間のために: Hammerhead schools within sight of Honshu, energetic Kuroshio drifts, big-fish traffic

地形: Current-swept rock ridges and boulder slopes falling into blue water

流れ（カレント）: The Kuroshio's edge washes the rocks; currents shift mid-dive and the guides read them constantly.

エントリー: Boats run from Shimoda to the lighthouse rocks offshore; negative entries and group drifts are standard, and marginal weather cancels quickly.

危険生物・リスク: Strong shifting current, exposed offshore position, and depth creep while shadowing schools; surface markers required.

ナイトロックス: ここでは効果的です——このエリアのプロファイルは、ナイトロックスが無減圧潜水時間を有意に延ばせる水深帯にあります（適切なトレーニングを受けていることが前提です）。