70 ILCS 1825/4.21

The District may acquire, erect, construct, maintain and operate aquariums, museums and other edifices for the collection and display of objects pertaining to natural history or the arts and sciences; and may permit the directors or trustees of any corporation or society organized for the erection, construction, maintenance and operation of any aquarium, museum or other such edifice to perform such erection, construction, maintenance and operation on or within any property now or hereafter owned by or under the control or supervision of the District. The District may contract with any such directors or trustees relative to such acquisition, erection, construction, maintenance and operation. The District may charge, or may authorize such directors or trustees to charge an admission fee, the proceeds of which shall be devoted exclusively to such erection, construction, maintenance and operation.