II Samuel 24:5 Midrash

וַיַּעַבְר֖וּ אֶת־הַיַּרְדֵּ֑ן וַיַּחֲנ֣וּ בַעֲרוֹעֵ֗ר יְמִ֥ין הָעִ֛יר אֲשֶׁ֛ר בְּתוֹךְ־הַנַּ֥חַל הַגָּ֖ד וְאֶל־יַעְזֵֽר׃

And they passed over the Jordan, and pitched in Aroer, on the right side of the city that is in the middle of the valley of Gad, and unto Jazer;