 Iron Horse Regional Trail pedestrian bridge over Ygnacio Valley Road | |
 | |
| Maintained by | Walnut Creek, Concord, Pittsburg, and Contra Costa County, California |
|---|---|
| Length | 15.66 mi (25.20 km) |
| Southwest end | Parkside Drive in Walnut Creek |
| Major junctions |   I-680 / SR 24 in Walnut Creek SR 4 in Pittsburg |
| Northeast end | E 3rd St in Pittsburg |
Ygnacio Valley Road is a major arterial road in central Contra Costa County, California. It extends from Interstate 680 and SR 24 in Walnut Creek to SR 4 in Pittsburg. The road passes through Concord and borders Clayton. In the northern half of the route, it is also known as Kirker Pass Road and then Railroad Avenue. It is listed, but not signed, as Hillside Avenue at its southwest terminus.
