Chain of Rocks Bridge
The pin is a point inside the NPS boundary polygon, not a surveyed location.
Why it's listed
Spanning the Mississippi River near its meeting with the Missouri, this steel truss bridge runs more than a mile between Madison County, Illinois, and northern St. Louis. Built from 1927 to 1929 and designed by St. Louis engineer Baxter L. Brown, it is best known for a thirty-degree bend near mid-river, added after boatmen protested and the War Department required a change so the piers would line up with nearby water intake towers. In 1936 it became part of US Route 66, carrying travelers into St. Louis from the north until the late 1960s, when a new Interstate 270 bridge opened upstream. The city of Madison closed the old span in 1968, and it sat idle for years while demolition was considered. A nonprofit group led its conversion to a pedestrian and bicycle path, which opened in 1999. It is valued for its engineering and its role in Route 66 history.
Significance in brief: The bridge is significant under Criterion A as a notable link in the US Route 66 corridor, serving as the widest river crossing on the route and an entry to St. Louis. Under Criterion C it is an outstanding example of large-scale 1920s highway bridge engineering, with long cantilevered steel trusses on tapered concrete piers. Its bend, added to ease river navigation, makes it distinctive.
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 06001091, listed December 1, 2006. Summary generated October 2026 (model claude-sonnet-5-5, prompt v1.0-2026-10-29, confidence high).
Key facts
| Address | West Chain of Rocks Rd., Madison |
|---|---|
| County | Madison County |
| Listed | December 1, 2006 |
| Reference number | 06001091 |
| Resource type | Structure |
| Period of significance | 1929-1956 |
| Architect / builder | Brown, Baxter L., Engineer; Union Bridge and Construction Company of New York, and the American Bridge Company, Builders |
| Architectural style | OTHER: Warrant Truss |
| Criteria |
|
| Areas of significance | Transportation, Engineering |
| Level of significance | National |
| Status (as stated in the nomination) | Closed to vehicles in 1968, then repaired and reopened in 1999 as a pedestrian and bicycle bridge; the toll house has been demolished. |
| Acreage | 12.6 |
| Coordinates | 38.76046, -90.17200 (NPS GIS) |
What listing means for this property
For a publicly owned building or structure, listing mainly matters when federal funds, permits or licences are involved: projects then go through Section 106 review so effects on the property are considered. Listing also strengthens applications for preservation grants and, for leased income-producing uses, can enable the federal rehabilitation tax credit.
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 06001091.
- Nomination form (PDF, National Archives) — catalog entry
- Wikipedia article (used for cross-checking only; text not reproduced here)
- Wikidata Q592557
- This listing as JSON
Last updated October 2026. Found an error? See the editorial policy for how to report it.