Genesis 8:20

8:20 Noah built an altar to the Lord. He then took some of every kind of clean animal and clean bird and offered burnt offerings on the altar.

Genesis 12:7-8

12:7 The Lord appeared to Abram and said, “To your descendants I will give this land.” So Abram built an altar there to the Lord, who had appeared to him.

12:8 Then he moved from there to the hill country east of Bethel and pitched his tent, with Bethel on the west and Ai on the east. There he built an altar to the Lord and worshiped the Lord.