Ezekiel 42:3, 19-20

On one side of the building was the twenty-cubit-wide plaza of the inner courtyard. On the other side was the paved walkway of the outer courtyard. The building itself was three stories high and had balconies.

Then he turned to the west side and measured it as five hundred cubits by the measuring rod. And so he measured the temple compound on all four sides. The wall of the temple compound was five hundred cubits square, to mark the boundary between what was holy and what was common.