Indiana Code Title 8. Utilities and Transportation § 8-15-3-7

(1) an express highway, limited access facility, superhighway, bridge, tunnel, or motor way, including express lanes and managed lanes, constructed under this chapter or IC 8-15.7 or, subject to section 10 of this chapter, converted to a tollway under IC 8-23-7-22;

(2) any bridge, tunnel, overpass, underpass, interchange, structure, ramp, access road, service road, entrance plaza, approach, tollhouse, utility corridor, toll gantry, rest stop, service station, or administration, storage, or other buildings or facilities, including temporary facilities and buildings, facilities, and structures that will not be tolled, that the department considers appurtenant to or necessary or desirable for the financing, construction, operation, or maintenance of one (1) or more of the items described in subdivision (1);

(3) any subsequent improvement, betterment, enlargement, extension, or reconstruction of one (1) or more items described in this section, including any nontolled part, that are separately designated by name or number;

(4) a project connecting the state of Indiana with an adjacent state;  or

(5) any combination of items or projects described in subdivisions (1) through (4).