765 ILCS 205/3
The acknowledgment and recording of such plat, or the acknowledgment and the filing of the same shall be held in all courts to be a conveyance in fee simple of such portions of the premises platted as are marked or noted on such plat as donated or granted to the public, or any person, religious society, corporation or body politic, and as a general warranty against the donor, his or her heirs and representatives, to such donee or grantee, for their use or for the use and purposes therein named or intended, and for no other use or purpose; and the premises intended for any street, alley, way, common or other public use in any city, village or town, or addition thereto, shall be held in the corporate name thereof in trust to and for the uses and purposes set forth or intended.
765 ILCS 205/3