SMS Markgraf

Markgraf fought at Jutland and now lies almost fully inverted in the deepest water of the German fleet, her upturned hull rising from around 45 m to the mid-twenties. The scale registers slowly: a wall of riveted plate longer than a football pitch, rudders raised toward the light, and along the port side the crushed gallery where casemate guns and portholes emerge from the shadows. This is a dive of atmosphere rather than easy sightseeing — dark, deep and unforgiving of poor planning — and for many wreck divers it is the single best thing in British waters.

その瞬間のために: Dreadnought scale in the gloom, casemate guns along the hull side, the fleet's most prestigious tick

地形: A Konig-class battleship lying nearly upside down on a silt-and-shell seabed at about 45 m

エントリー: Shotline descent from Stromness charter boats; the deepest and most demanding of the German fleet.

危険生物・リスク: Depth, darkness, silt and inverted orientation that disorients; penetration is a technical-team undertaking only.

保全: A scheduled monument: nothing is removed, nothing disturbed. A century of salvage history already scars the fleet — divers should not add to it.

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）。