Putting a mine on a land-sea tile

[KorutZelva]

Let's say as the Turk I put a mine at the mouth of the Dardanelle. Basically doesn't it block the entente ship forever?

The hex is occupied so a land unit can't enter (or attack the mine) and since it's also a land hex, ships can't enter to sweep the mine since they need to own the hex to enter...

[KorutZelva]

Turkish land units can move through it freely though. I could see a use to plump one right next to Istanbul that way it cannot get squeezed by two amphibious units limiting its reinforcement to str 5.

[operating]

If OE surrenders do those mines stay in place? Can any or all faction's navies pass through the Dardanelles from the Black Sea to the Med, or vice-versa should OE surrender without giving up land hexes?

[KorutZelva]

It disappears. That I know because Ashfall had mine the entrance of the Kiel canal with the Russians and they vanished after the peace treaty. Interestingly they can mine enemy owned Hex... I wonder if that count as a unit for land unit surrounding purpose...