I have overheard the story from an US soldier that during the Pacific War the Japanese mounted a defense in an old medieval castle. The Americans asked for support from a battleship. The battleship successfully shelled the fortress only to find out that the castle was able to withstand battleship fire!
Now if you know how big battleship guns are...you, me and the other people are thinking "he is pulling our leg". But he insisted that this is true and they finally called a special ship with 15" guns and extreme high-explosive
grenades shells which was able to tear the castle down.
Does anyone know if there is a grain truth in this story ? Google Fu failed.