Monticello Courthouse Square Historic District
Why it's listed
Monticello's Courthouse Square district covers roughly sixteen blocks of the Piatt County seat in east-central Illinois. Most of it follows the Original Town plat of 1841. The Piatt County Courthouse sits at the center, surrounded by densely built two-story storefronts, with more scattered development to the north and south. Of 85 resources, 77 contribute: 73 buildings, three structures (two 1934 bridges and the 1935 water tower) and one object, a courtyard wall. Italianate is the dominant style, with twenty-five buildings showing its influence. Other styles include Romanesque Revival, as in the Town Hall, Opera House and Allerton Library; Classical Revival; Late Gothic Revival; and Art Moderne. The period of significance runs from about 1856, when the J.C. Johnson/I.O.O.F. Building went up, to 1959, when the Monticello Professional Building was finished. The district's value lies in how fully the courthouse square pattern and its commercial and civic buildings survive from the nineteenth century.
Significance in brief: The district keeps the building pattern of a courthouse square framed by dense two-story storefronts, largely intact from the mid-to-late 19th century. It shows the growth of the county seat through Italianate, Romanesque Revival, Classical Revival and later styles. The nomination also stresses its governmental and civic buildings, such as the courthouse and the Town Hall/Opera House/Allerton Library.
Machine-generated summary. This summary was generated by a language model from the official nomination document and has not been reviewed line by line by an editor. It may contain errors. Check the source document before relying on any detail. Source: nomination document (PDF) · National Archives catalog entry. NRHP reference 08000400, listed November 5, 2009. Summary generated October 2026 (model claude-sonnet-5-5, prompt v1.0-2026-10-29, confidence medium).
Key facts
| Address | Roughly bounded by Market, RR tracks, N. Hamilton, Independence & Marion Sts., Monticello |
|---|---|
| County | Piatt County |
| Listed | November 5, 2009 |
| Reference number | 08000400 |
| Resource type | District |
| Period of significance | c. 1856-1959 |
| Architect / builder | Louis A. Simon, Supervising Architect (U.S. Post Office); R.Z. Gill and Seeley Brown (Town Hall/Opera House/Allerton Library); Jackson, Cook and Dixon (Monticello Professional Building) |
| Architectural style | Italianate, Classical Revival, Romanesque Revival |
| Areas of significance | Commerce, Politics/Government, Architecture |
| Level of significance | Local |
| Status (as stated in the nomination) | Commercial and governmental uses continue today; the district substantially retains its mid-to-late 19th-century pattern, and eight resources are noncontributing. |
| Acreage | 28 |
| Coordinates | 40.02544, -88.57175 (NPS GIS) |
What listing means for this property
This is a historic district. Buildings within its boundary are either contributing (they add to the district's significance) or non-contributing. Owners of contributing income-producing buildings can claim the 20% federal rehabilitation tax credit; homeowners should look at state credits. National Register districts impose no design review by themselves; a local historic district ordinance, if one exists, does (the difference explained).
General information, not legal or tax advice. Rules change; confirm with your State Historic Preservation Office or a qualified adviser.
Sources and further reading
- National Park Service, National Register of Historic Places database (snapshot May 2026), reference 08000400.
- Nomination form (PDF, National Archives) — catalog entry
- Wikipedia article (used for cross-checking only; text not reproduced here)
- Wikidata Q18217081
- This listing as JSON
Last updated October 2026. Found an error? See the editorial policy for how to report it.