St. Charles Seminary and Chapel
Also known as: St. Charles Borromeo Seminary and Chapel
Why it's listed
Set on a working farm just south of Carthagena in Mercer County, this religious complex centers on a 1906 Romanesque chapel and a large Gothic Revival seminary built between 1919 and 1925. The seminary, designed by Herman Gaul of Chicago, has a facade stretching 371 feet, with a five-story octagonal dome over the entrance. The chapel was built by the DeCurtins Brothers of Carthagena. The site served as the training center for priests of the Society of the Most Precious Blood from 1860 to 1968, and hundreds were ordained here. It grew over time with a convent, power plant, infirmary, print shop and farm buildings, and it includes a cemetery, grotto and stations of the cross from 1901, two ponds and a tree-lined drive. The property occupies the site where an earlier school for free Black students, built in 1836, was acquired by the society. Today the building is used mainly as a retirement home.
Significance in brief: It was the training center for the Fathers of the Society of the Most Precious Blood from 1860 until 1968. The 1919-1925 High Gothic seminary is described as possibly the most exquisite building in the county, and the 1906 chapel as an excellent example of Romanesque architecture. The surrounding farm, cemetery, grotto and landscaped grounds are treated as integral to the property.
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 79002840, listed July 26, 1979. Summary generated October 2026 (model claude-sonnet-5-5, prompt v1.0-2026-10-29, confidence medium).
Key facts
| Address | .5 mi. S of Carthagena, off OH 127, Carthagena |
|---|---|
| County | Mercer County |
| Listed | July 26, 1979 |
| Reference number | 79002840 |
| Resource type | Building |
| Architect / builder | Chapel: DeCurtins Brothers of Carthagena; seminary: Herman Gaul of Chicago |
| Architectural style | Chapel: Romanesque; seminary: Late Gothic Revival (High Gothic) |
| Areas of significance | Architecture |
| Level of significance | State |
| Status (as stated in the nomination) | Described as in good condition and used primarily as a retirement home; the form also lists lack of use as an endangerment. |
| Acreage | 150 |
| Coordinates | 40.43242, -84.56596 (NPS GIS) |
What listing means for this property
Religious properties are listed for their architectural or historical significance, not their religious use. Listing is honorary and does not restrict the congregation's use of the building. The federal rehabilitation credit is generally unavailable unless part of the building is income-producing; some state programmes and preservation grants do cover religious buildings. Federal funding or permits trigger Section 106 review.
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 79002840.
- Nomination form (PDF, National Archives) — catalog entry
- Wikipedia article (used for cross-checking only; text not reproduced here)
- Wikidata Q7587535
- This listing as JSON
Last updated October 2026. Found an error? See the editorial policy for how to report it.