'Altar' in the Bible

Did I not choose them from all the tribes of Israel to be My priests, to go up to My altar, to burn incense, to carry an ephod before Me; and did I not give to the house of your father all the fire offerings of the sons of Israel?

Yet I will not cut off every man of yours from My altar so that your eyes will fail from weeping and your soul grieve, and all the increase of your house will die in the prime of life.

Then his return was to Ramah, for his house was there, and there he judged Israel; and he built there an altar to the Lord.

And Saul built an altar to the Lord; it was the first altar that he built to the Lord.