Ezekiel 40:17-21

Then brought he me into the outward court, and, lo, there were chambers, and a pavement made for the court round about: thirty chambers were upon the pavement.

And the pavement by the side of the gates over against the length of the gates was the lower pavement.

Then he measured the breadth from the forefront of the lower gate unto the forefront of the inner court without, an hundred cubits eastward and northward.

And the gate of the outward court that looked toward the north, he measured the length thereof, and the breadth thereof.

And the little chambers thereof were three on this side and three on that side; and the posts thereof and the arches thereof were after the measure of the first gate: the length thereof was fifty cubits, and the breadth five and twenty cubits.