Ezekiel 42:9

And from under these chambers was the entry on the east side, as one goeth into them from the utter court.

Cross-reference

Ezekiel 42:12 details the doors of chambers on the south side — continuing the description of entrances started here.

Ezekiel 46:19 describes the entrance to the holy chambers for priests — directly expanding on the entrance from the outer court mentioned here.