Ezekiel 43:12-13

This is the law of the temple: the whole territory on the top of the mountain all around shall be most holy. Behold, this is the law of the temple. “These are the measurements of the altar by cubits (the cubit being a cubit and a handbreadth): its base shall be one cubit high and one cubit broad, with a rim of one span around its edge. And this shall be the height of the altar