1 Kings 12:28, 30, 33

Whereupon the king took counsel, and made two calves of gold, and said unto them, It is too much for you to go up to Jerusalem: behold thy gods, O Israel, which brought thee up out of the land of Egypt.

And this thing became a sin: for the people went to worship before the one, even unto Dan.

So he offered upon the altar which he had made in Beth-el the fifteenth day of the eighth month, even in the month which he had devised of his own heart; and ordained a feast unto the children of Israel: and he offered upon the altar, and burnt incense.