Ezekiel 40:17-19

17Then he brought me into the outer court, and, lo, there were chambers, and a pavement made for the court all around: thirty chambers were upon the pavement. 18And the pavement by the side of the gates was as wide as the length of the gates; was to the lower pavement. 19Then he measured the breadth from the front of the lower gate to the front of the inner court on the other side, an hundred cubits eastward and northward.1