Zechariah 5:11

וַיֹּאמֶר אֵלַי לִבְנוֹת לָה בַיִת בְּאֶרֶץ שִׁנְעָר וְהוּכַן וְהֻנִּיחָה שָּׁם עַל-מְכֻנָתָהּ

He said unto me, “To build a house for it in the land of Shinar. When it is prepared, it will be set there on its foundation.”

Shinar is Babylonia. The Radak refers us back to the prophecy in Jeremiah chapter 29. There, the prophet Jeremiah tells the Jews that they might as well get comfortable in Babylonia – build houses and live in them, plant gardens and eat their fruit, get married and have children, then marry off those children – because it’s going to be a long exile there. Those who did not return to rebuild the Temple with Ezra were never going to return. (Sure enough, Babylonia ended up being the center of Jewish life throughout the Talmudic and Gaonic periods – a span of close to 900 years!)