Idaho State Highway 78
# Idaho State Highway 78

State Highway 78 (SH-78) is a state highway in Idaho from SH-55 in Marsing to I-84 Business Loop in Hammett

## Route description

SH-78 starts at the intersection with SH-55 in Marsing and provides access to sites south of the Snake River from there to Bruneau and a few along the north side via SH-167 from Grand View. SH-78 provides access to Bruneau Dunes State Park and itself crosses the Snake into Elmore County before reaching its eastern terminus at Hammett.

## History

The basic route of today's SH-78 from Marsing to Bruneau was in place as early as the mid-1930s, mostly as unimproved roads with a few all-weather gravel segments near Bruneau, Grand View and north of Murphy (a segment originally part of SH-45), and some paved segments near Marsing as of the 1937 map.

## Major junctions

| County | Location | mi | km | Destinations | Notes |
| - | - | - | - | - | - |
| Owyhee | Marsing | 0.000 | 0.000 | SH-55 – Marsing, Nampa, Boise, Eagle | US-95 is about 2 miles (3.2 km) south on SH-55 |
| Owyhee | ​ | 19.775 | 31.825 | SH-45 north – Nampa | |
| Owyhee | Murphy | 34.105 | 54.887 | Silver City Road | National historic mining district and former Owyhee County seat about 25 miles (40 km) south |
| Owyhee | Grand View | 59.782 | 96.210 | SH-167 north – Mountain Home AFB, Mountain Home | Access to Simplot feed lot, USAF Recreation Area at C. J. Strike Dam, Simco Road |
| Owyhee | ​ | 76.004 | 122.317 | SH-51 south – Grasmere, Elko | Southern end of SH-51 overlap |
| Owyhee | Bruneau | 82.680 | 133.061 | SH-51 north – Mountain Home | Northern end of SH-51 overlap |
| Owyhee | Bruneau | 84.360 | 135.764 | Bruneau Dunes State Park | protected sand dunes |
| Snake River | Snake River | 94.664 | 152.347 | Snake River Bridge Owyhee–Elmore county line | Snake River Bridge Owyhee–Elmore county line |
| Elmore | Hammett | 98.640– 99.720 | 158.746– 160.484 | I-84 BL – Mountain Home, Boise, Twin Falls | Overlap with I-84 Bus. |
| 1.000 mi = 1.609 km; 1.000 km = 0.621 mi Concurrency terminus ||||||
