List of National Historic Landmarks in Illinois

Also added are two sites that were once National Historic Landmarks before having their designations removed.

The National Park Service determines which properties meet NHL criteria and makes nomination recommendations after an owner notification process.

[1] The Secretary of the Interior reviews nominations and, based on a set of predetermined criteria, makes a decision on NHL designation or a determination of eligibility for designation.

[2] Both public and privately owned properties can be designated as NHLs.

This designation provides indirect, partial protection of the historic integrity of the properties via tax incentives, grants, monitoring of threats, and other means.