Illinois Route 4-North of Auburn
Also known as: Sbi 4; State Aid 6
Why it's listed
North of Auburn, in Sangamon County, Illinois, two surviving pieces of an early highway preserve how the road between Chicago and St. Louis was once built. One is a 1,277-foot stretch of 16-foot-wide Portland cement pavement, completed by 1921 as part of State Bond Issue 4 and later carried the first Route 66 alignment from 1926 to 1930. After a 1932 realignment bypassed it, the pavement stayed largely unchanged, and its curve is now abandoned. The other is a 1.53-mile road that was widened to 20 feet and surfaced with brick in 1932, known today as the Auburn Brick Road. Two single-span reinforced concrete bridges built in 1920 carry the road over Panther Creek. The route was listed for its engineering significance, as representative of Illinois road-building standards between 1920 and 1932. Its rural setting, lane widths, grading and bridges remain much as they were during that period, and both segments are still open to traffic.
Significance in brief: The segments are argued to be good, locally significant examples of early 1920s through 1932 road construction, meeting Criterion C for engineering. The concrete stretch represents the earliest 1926-1930 Route 66 alignment in Illinois, and the brick road reflects a method of road building used in the early twentieth century. Both retain their original width, cross-section, materials and rural setting.
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 98000979, listed August 6, 1998. Summary generated October 2026 (model claude-sonnet-5-5, prompt v1.0-2026-10-29, confidence medium).
Key facts
| Address | Curran and Snell Rd., Auburn |
|---|---|
| County | Sangamon County |
| Listed | August 6, 1998 |
| Reference number | 98000979 |
| Resource type | Structure |
| Period of significance | 1920 - 1932 |
| Architect / builder | Unknown |
| Architectural style | Other: Concrete Road; Brick Road |
| Criteria |
|
| Areas of significance | Engineering |
| Level of significance | Local |
| Status (as stated in the nomination) | Both segments are still in use as public roads, though in varying degrees of disrepair; the 677-foot concrete curve is abandoned and has no road designation. |
| Acreage | 7.5 |
| Coordinates | 39.61663, -89.74990 (NPS GIS) |
What listing means for this property
National Register listing is honorary: it recognises significance and does not restrict what a private owner may do without federal money or permits. It unlocks the 20% federal rehabilitation tax credit for income-producing buildings, state credits in many states, and Section 106 review when federal agencies are involved. See what listing means in practice.
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 98000979.
- Nomination form (PDF, National Archives) — catalog entry
- Wikidata Q113681776
- This listing as JSON
Last updated October 2026. Found an error? See the editorial policy for how to report it.