Isaiah 19:18

In that day, the populations of five Egyptian cities would speak Hebrew out of deference to the Jews and commitment to Yahweh. While five is not many, Isaiah evidently meant that as many as five (quite a few in view of Egypt’s previous massive idolatry), and perhaps more, would do so (cf. Genesis 11:1). One of these five would be called the City of Destruction (Heb. heres), perhaps because of the destruction that God would bring to Egypt. Another possibility is that "destruction" should read "sun" (Heb. heres with a het rather than a he). In this case the City of the Sun, On (Gr. Heliopolis), is in view. On was a center of the worship of the sun god in Egypt, so this may point to an end of idolatry there.