{"nrhp_refnum":"02000461","name":"Route 66 by Carpenter Park","other_names":[],"category":"structure","location":{"address":"Old Route 66 bet. Cabin Smoke Trail and N bank of the Sangamon R.","address_restricted":false,"city":"Springfield","county":"Sangamon County","state":"IL","lat":39.87265232800007,"lon":-89.61435558899996,"geom_source":"nps_gis"},"listed_date":"2002-05-09","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Transportation","Engineering"],"significance_levels":["local"],"summary":{"what_it_is":"A quarter-mile segment of concrete and gravel road near Carpenter Park, between Cabin Smoke Trail in Sherman and the north bank of the Sangamon River in Springfield, Sangamon County, Illinois. It was built in 1922 as part of State Bond Issue 124.","why_significant":"The segment carried U.S. Route 66 traffic from 1926 until a new four-lane alignment opened to the east in 1936, which gives it significance under transportation. It is also significant for engineering as a representative example of 1920s state-aided highway design standards. Because it has not carried traffic or been resurfaced since 1936, its original cross-section, curbs and pavement remain largely intact.","narrative":"A quarter-mile stretch of early concrete highway runs beside Carpenter Park, a 437-acre nature preserve, between Cabin Smoke Trail in Sherman and the Sangamon River in Springfield, Illinois. Built in 1922 under State Bond Issue 124, the 16-foot-wide road is paved with a mix of cement and gravel and has curbs, expansion joints every 30 yards, and short gravel shoulders. When Route 66 was created in 1926, it followed this paved road and its iron truss bridge over the river. Traffic used it until 1936, when a wider four-lane alignment opened a few yards east. The old road was then closed and left unmaintained, which preserved its original cross-section, curbs and pavement. It is significant for its link to Route 66 and as a typical example of 1920s highway engineering. Visitors can now hike its surviving length without vehicle traffic, in a wooded setting shielded from modern development.","period_of_significance":"A: 1926-1936; C: 1922-1936","architect_builder":null,"architectural_style":"Other: Concrete Road","criteria":["A","C"],"status_note":"Closed to traffic since 1936 and abandoned by the state; the pavement is original and cracked in places. Only a water district maintenance truck has occasional access, and hikers can walk it.","vacant_flag":null,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:55:37.596799-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/opastorage/live/38/8914/28891438/content/electronic-records/rg-079/NPS_IL/02000461.pdf"},"photo":null,"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/28891438","wikipedia":null,"wikidata":null},"indexable":true,"url":"https://nationalhistoricalregister.com/illinois/sangamon-county/route-66-by-carpenter-park-02000461/"}