Surah 2:22
"(He it is) who made the earth as a couch for you, and the sky a dome, and sent down water from the sky, by means of which He produced fruits as a provision for you. So do not set up rivals to God, when you know (better)."
Sky is a Tent/Dome
A common myth at the time of the Quran's composition was that the sky or heavens were held up with pillars. Many Bedouin people living in Arabia imagined the sky as a large tent covering, similar to the tents they used. The author repeats this myth by describing the sky as being "raised" above the earth.
Scientific Error
The Earth is Flat.