'Castle' in the Bible

The words of Nehemiah son of Hacaliah:Now it happened in the month of Chislev, in the twentieth year [of the Persian king], as I was in the capitol of Susa,

I put my brother Hanani, with Hananiah the commander of the fortress, in charge of Jerusalem, for Hananiah was a more faithful and God-fearing man than many [of the others].