Ezekiel 40:35-38

Then he brought me to the north gateway and measured it according to these same measurements— also its gate chambers, its gateposts, and its archways. It had windows all around; its length was fifty cubits and its width twenty-five cubits. Its gateposts faced the outer court, palm trees were on its gateposts on this side and on that side, and going up to it were eight steps. There was a chamber and its entrance by the gateposts of the gateway, where they washed the burnt offering.