Ezekiel 43:14-16

14From the gutter on the ground up to the lower ledge that goes around the altar it is two cubits high, and the ledge is a cubit wide. From this lower ledge to the upper ledge that goes around the altar it is four cubits high, and that ledge is also a cubit wide. 15Above that, the altar hearth is four cubits high, and four horns project upward from the hearth. 16The altar hearth is square, twelve cubits long and twelve cubits wide.