הֲרָרִי֙ בַּשָּׂדֶ֔ה חֵילְךָ֥ כָל־אוֹצְרוֹתֶ֖יךָ לָבַ֣ז אֶתֵּ֑ן בָּמֹתֶ֕יךָ בְּחַטָּ֖את בְּכָל־גְּבוּלֶֽיךָ׃
O ma montagne [qui te dresses] dans la plaine, tes richesses, tous tes trésors, je les livrerai au pillage, ainsi que tes hauts-lieux, à cause des péchés commis sur tout ton territoire.
Rashi
You, who sit upon the mountain in the field Jerusalem that is situated on the mountain of the plain. All around the city is a fielded plain. The structure of הֲרָרִי is like עֲרָבִי, called so because he dwells in the plain (עֲרָבָה) (montanyers in O.F), mountain dwellers (other versions: a mountain dweller).
Rashi
Your high places are made for sin Your high places are made in sin for the purpose of idolatry within all your borders.