Ezekiel 40:6-7

6Then he went to the gate which faced the east and went up its [seven] steps and measured the threshold of the gate, one rod in width; and the other threshold [of the gate inside the thick wall] was one rod in width.

7The guardroom was one rod long and one rod wide, and [the space] between the guardrooms was five cubits. And the threshold of the gate by the porch (portico) of the gate facing inward was one rod.