Second Temple: The Altar of Burnt Offering The Altar of Burnt Offering was made of stone not fashioned by man's hands. It stood in the Court of the Priest's near the entrance to the Holy Place.
The Altar in Herod's Temple by Edersheim
The most prominent object in the Court of the Priests was the immense altar of unhewn stones, * a square of not less than 48 feet, and, inclusive of 'the horns,' 15 feet high.
They were 'whitened' twice a year. Once in seven years the high-priest was to inspect the Most Holy Place, through an opening made from the room above. If repairs were required, the workmen were let down through the ceiling in a sort of cage, so as not to see anything but what they were to work at.
All around it a 'circuit' ran for the use of the ministering priests, who, as a rule, always passed round by the right, and retired by the left. *
The three exceptions to this are specially mentioned in the Talmud. The high-priest both ascended and descended by the right.
As this 'circuit' was raised 9 feet from the ground, and 1 1/2 feet high, while the 'horns' measured 1 1/2 feet in height, the priests would have only to reach 3 feet to the top of the altar, and 4 1/2 feet to that of each 'horn.' An inclined plane, 48 feet long by 24 wide, into which about the middle two smaller 'descents' merged, led up to the 'circuit' from the south. Close by was the great heap of salt, from which every sacrifice must be salted with salt. *
Also a receptacle for such sin-offerings of birds as had become spoiled. This inclined plane was kept covered with salt, to prevent the priests, who were barefooted, from slipping.
On the altar, which at the top was only 36 feet wide, three fires burned, one (east) for the offerings, the second (south) for the incense, the third (north) to supply the means for kindling the other two. The four 'horns' of the altar were straight, square, hollow prominences, that at the south-west with two openings, into whose silver funnels the drink-offerings, and, at the Feast of Tabernacles, the water from the Pool of Siloam, were poured. A red line all round the middle of the altar marked that above it the blood of sacrifices intended to be eaten, below it that of sacrifices wholly consumed, was to be sprinkled. The system of drainage into chambers below and canals, all of which could be flushed at will, was perfect; the blood and refuse being swept down into Kedron and towards the royal gardens. Finally, north of the altar were all requisites for the sacrifices--six rows, with four rings each, of ingenious mechanism, for fastening the sacrifices; eight marble tables for the flesh, fat, and cleaned 'inwards'; eight low columns, each with three hooks, for hanging up the pieces; a marble table for laying them out, and one of silver for the gold and silver vessels of the service. https://www.bible-history.com/jewishtemple/JEWISH_TEMPLEEdersheim__Within_the_Holy_Place.htm
The Altar in Herod's Temple ISBE
In the priests' court the principal object was the great altar of burnt offering, situated on the old site--the Sakhra--immediately in front of the porch of the temple (at 22 cubits distance--the space "between the temple and the altar" of Mt 23:35). The altar, according to the Mishna (Mid., iii.1), was 32 cubits square, and, like Ezekiel's, rose in stages, each diminishing by a cubit: one of 1 cubit in height, three of 5 cubits, which, with deduction of another cubit for the priests to walk on, left a square of 24 cubits at the top. It had four horns. Josephus, on the other hand, gives 50 cubits for the length and breadth, and 15 cubits for the height of the altar (BJ, V, v, 6)--his reckoning perhaps including a platform (a cubit high?) from which the height is taken (see ALTAR). The altar was built of unhewn stones, and had on the South a sloping ascent of like material, 32 cubits in length and 16 in width. Between temple and altar, toward the South, stood the "laver" for the priests. In the court, on the north side, were rings, hooks, and tables, for the slaughtering, flaying and suspending of the sacrificial victims.
The Altar of Sacrifice in Herod's Temple
Inside the court of the priests and just after the entrance into the Temple area, stood the great Altar of Burnt Offering, it could be seen from a distance. The Altar of Burnt Offering was made of unwrought stone, 30 cubits (45 feet) in length and breadth, and 15 cubits (22 feet) high. West of this was the Temple, and between the Holy Place and the altar stood the laver of cleansing. https://www.bible-history.com/jewishtemple/JEWISH_TEMPLEThe_Altar_of_Sacrifice.htm