Ezekiel 40:35-38

Then he brought me to the north gate; and he measured it according to those same measurements, with its guardrooms, its side pillars and its porches. And the gate had windows all around; the length was fifty cubits and the width twenty-five cubits. Its side pillars were toward the outer court; and palm tree ornaments were on its side pillars on each side, and its stairway had eight steps. A chamber with its doorway was by the side pillars at the gates; there they rinse the burnt offering.