I-580 highlighted in red
|Maintained by NDOT|
|Length||35.187 mi  (56.628 km)|
|Existed||October 27, 1978–present|
|History||Number approved on October 27, 1978; constructed in phases 1964–2017; signed in 2012|
US 50 / US 395 / US 395 Bus. in Carson City
|North end||I‑80 / US 395 in Reno|
Interstate 580 (I-580) is a 35.187-mile (56.628 km) Interstate Highway in northwestern Nevada. It runs concurrently with U.S. Route 395 (US 395) from an intersection with US 50 near the southern boundary of Carson City to the Reno Spaghetti Bowl interchange with I-80 in Reno. The freeway provides a high-speed direct route between Lake Tahoe and Carson City to Reno and I-80.
Construction on a freeway between Carson City and Reno was planned since 1956, but construction did not occur until 1964. The freeway opened in sections, with the final section opening in 2017. The I-580 designation was approved in 1978, but the freeway was not signed as such until the portion between Reno and Carson City was completed in 2012. While the entire length of the freeway was opened to traffic by August 2017, there are plans for a grade-separated interchange at the southern terminus with US 50, but this interchange has been postponed with no scheduled completion date.
I-580 runs from an intersection with US 50 in Carson City to an interchange with I-80 near downtown Reno. The only portion remaining to be constructed is the interchange at the freeway's southern terminus. Within Reno, the freeway is designated as the Martin Luther King, Jr., Freeway. Within Carson City, the freeway is designated the Carson City Deputy Sheriff Carl Howell Memorial Freeway, in honor of a sheriff's officer who was shot to death while attempting to rescue a victim of domestic violence from her house.  
The freeway begins at the junction of US 395 with the Lake Tahoe leg of US 50 and follows the eastern edge of Eagle Valley, where most of the population of Carson City lives. The highway loosely follows the former alignments of Edmonds Drive and Lompa Lane along the eastern half of the city, which were relocated or truncated to make room for the freeway.
After rejoining the original alignment of US 395 near the Carson Tahoe Regional Medical Center, the highway crests Lakeview Hill to enter the Washoe Valley. The portion of I-580/US 395 and US 395 Alternate through Washoe Valley are prone to high crosswinds and, as such, the highways are frequently closed to high-profile vehicles. During prohibited times, trucks are rerouted to Eastlake Boulevard and US 395 Alternate (US 395 Alt.), which is the old route of US 395. The high wind area ends near the Bowers Mansion interchange near the northern end of the Washoe Valley.
Unlike the old US 395 which ran along the valley floor of Pleasant Valley, I-580 is routed in the mountains overlooking the valley. While traversing Pleasant Valley, the highway crosses the Galena Creek Bridge, the largest cathedral arch bridge in the world. Upon the descent from these mountains the highway cuts through the center of one of the largest geothermal power plants in the United States, Ormat Industries' Nevada Power station, just before entering Reno.
At the extreme southern edge of Reno, the highway has a junction with the Mount Rose Highway ( State Route 431, SR 431) and Geiger Grade ( SR 341), which connect the freeway with North Lake Tahoe and Virginia City, respectively. Upon entering Reno, the freeway proceeds in a generally northern direction, crossing Virginia Street, the old routing of US 395, several times. Along the way the freeway passes to the side of The Summit mall, Meadowood Mall and Reno–Tahoe International Airport. The elevated freeway also passes over a bus garage used by RTC Washoe, the local bus agency.  The I-580 designation ends at the Reno Spaghetti Bowl where the highway crosses I-80; however, the freeway continues on only as US 395, heading towards the north valley neighborhoods of Sun Valley, Lemon Valley and Stead before eventually crossing the California state line.
Development of the I-580/US 395 freeway has been in planning since 1956, but significant construction did not occur until 1964.  The freeway would be opened gradually over time, and would initially be constructed in two main separate sections before 2012.
The first segment of freeway constructed along I-580 was the Washoe Valley segment, which was constructed between 1964 and 1970 between present-day exit 50 (Bowers Mansion Road/Carson–Reno Highway) near Washoe City, south through Washoe Valley to just north of exit 43 (North Carson Street) in Carson City.
The Reno section was constructed between 1973 and 1996. In 1973, the section running between exit 72 (US 395 Business) to exit 67 (East Second Street/Glendale Avenue) in Reno opened to traffic. This section was extended south to exit 66 (Mill Street) in 1978, exit 65 (Plumb Lane/Villanova Drive) in 1979, exit 63 (South Virginia Street/Kietzke Lane) in 1981, exit 62 (Neil Road/Meadowood Mall Way) in 1986, exit 61 (South Virginia Street) in 1989, and exit 56 (Mount Rose Highway) in 1996. The Carson City section was constructed in the 2000s with construction of the Carson City Bypass project. The first phase completed the freeway from exit 43 (North Carson Street) south to exit 39 (East William Street) in 2006. The freeway was extended south to exit 38 (Fairview Drive) in 2009. On August 2, 2017, the final section of the freeway between exit 38 and exit 35 (South Carson Street) in Carson City opened to traffic.  However, the southern terminus of I-580 is currently an at-grade intersection, with future plans to convert the intersection to an interchange having no set timetable as of 2018. In 2012, the section between exit 56 (Mount Rose Highway) and exit 50 (Bowers Mansion Road/Carson–Reno Highway) south of Reno opened, connecting the two main segments together. After the completion of this section, the freeway south of exit 68 ( I-80) was finally signed as I-580, officially connecting Carson City to the Interstate Highway system. This left four other state capitals still not served by the Interstate Highway System: Dover, Delaware; Juneau, Alaska; Pierre, South Dakota; and Jefferson City, Missouri. 
The I-580 designation was first approved by the American Association of State Highway and Transportation Officials (AASHTO) on October 27, 1978; at the time, this route extended from I-80 to US 395 (South Virginia Street, at the current exit 63).   AASHTO approved the remainder of planned I-580, to the future southern terminus at US 395 south of Carson City, at its December 7, 1984, meeting.  Despite the route number being approved and being shown on some maps in the 1980s, I-580 was not signed along the Interstate until the freeway gap between Mount Rose Highway and Bowers Mansion Road was completed in 2012.
Phase 2B-4, the grade separation of I-580 at its southern terminus, has been postponed with no current set deadline.  Additionally, the routing for I-580 has been considered as a potential alignment for the extension of I-11. 
For other exits on US 395, see U.S. Route 395 in Nevada.
US 50 west / US 395 south / US 395 Bus. north (S. Carson Street) – South Lake Tahoe, Minden, Gardnerville
|Southern end of US 50/US 395 concurrency; southern terminus of I-580; at-grade intersection|
|4.57||7.35||39||US 50 east (E. William Street) – Dayton, Fallon||Northern end of US 50 concurrency|
|6.73||10.83||41||College Parkway||Serves Carson Airport and Western Nevada College|
|8.03||12.92||42||Arrowhead Drive||Northbound exit and southbound entrance; serves Carson Tahoe Regional Medical Center|
US 395 Bus. south (N. Carson Street)
|Southbound exit and northbound entrance; serves Carson Tahoe Regional Medical Center|
|Washoe Valley||9.37||15.08||44||Eastlake Boulevard (to US 395 Alt.)||Serves Washoe Lake State Park|
|Washoe City||15.46||24.88||50||Old US 395 ( US 395 Alt., Bowers Mansion Road, Carson–Reno Highway) – Washoe City||Serves Bowers Mansion|
|Pleasant Valley||19.50||31.38||Galena Creek Bridge|
|Reno||23.46||37.76||56||SR 431 (Mount Rose Highway) – North Lake Tahoe||Also serves SR 341 (Geiger Grade) to Virginia City|
|24.94||40.14||57B||S. Virginia Street south ( US 395 Alt. south) – Virginia City, Washoe City||Southbound exit and northbound entrance|
|25.40||40.88||57A||S. Virginia Street north ( US 395 Alt. north / US 395 Bus. north)||Southbound exit and northbound entrance|
|25.58||41.17||59||Damonte Ranch Parkway|
|26.89||43.28||60||South Meadows Parkway ( SR 426 west)|
|27.98||45.03||61||S. Virginia Street ( US 395 Alt. / US 395 Bus.)|
|30.19||48.59||62||Neil Road, Meadowood Mall Way|
|30.97||49.84||63||S. Virginia Street ( US 395 Bus.), Kietzke Lane||Southbound exit and northbound entrance|
|32.03||51.55||64||Moana Lane||Serves Reno-Sparks Convention Center|
|32.95||53.03||65||Plumb Lane ( SR 653), Villanova Drive, Reno-Tahoe International Airport||Signed as exits 65A (Villanova Drive, Plumb Lane) and 65B (airport) southbound|
|33.93||54.61||66||Mill Street||Serves Renown Regional Medical Center|
|34.46||55.46||67||E. Second Street, Glendale Avenue ( SR 648)|
US 395 north – Susanville
|Northern end of US 395 concurrency; northern terminus of I-580; signed as exits 68A (east) and 68B (west) northbound; I-80 exit 15; freeway continues as US 395|
|1.000 mi = 1.609 km; 1.000 km = 0.621 mi|
- Exits are numbered using cumulative mileage along US 395 from the California–Nevada border near Topaz Lake.
- Nevada Department of Transportation (January 2018). "State Maintained Highways of Nevada: Descriptions and Maps". Retrieved September 11, 2018.
- Munson, Jeff (December 8, 2015). "Stretch of Carson City Freeway Officially Named in Honor of Deputy Carl Howell". Carson Now. Retrieved December 8, 2015.
- Munson, Jeff (August 16, 2015). "Carson City Deputy Killed in the Line of Duty Identified". Carson Now. Retrieved December 8, 2015.
- "RTC Villanova Maintenance Facility Renovation and Expansion Project". City of Reno. p. 15. Retrieved October 4, 2018.
- Nevada Department of Transportation. "History & Overview". I-580 Extension Project website. Nevada Department of Transportation. Archived from the original on May 27, 2008. Retrieved September 11, 2008.
- Deach, Ben (August 2, 2017). "Freeway Extension to Save Drivers Time in Carson City". Reno, NV: KOLO-TV. Retrieved August 2, 2017.
- Rocha, Guy (February 28, 2006). "Carson City's freeway: a long time coming". Nevada Appeal. Retrieved June 24, 2018.
- Special Committee on U.S. Route Numbering (October 28, 1978). "Route Numbering Committee Agenda Showing Action Taken by the Executive Committee" (PDF) (Report). Washington, DC: American Association of State Highway and Transportation Officials. Retrieved November 7, 2014 – via Wikimedia Commons.
- "A drive on 395 is a drive on 580". Reno Gazette-Journal. December 13, 1978. p. 27. Retrieved June 24, 2018 – via Newspapers.com.
- Special Committee on U.S. Route Numbering (December 7, 1984). "Route Numbering Committee Agenda" (PDF) (Report). Washington, DC: American Association of State Highway and Transportation Officials. Retrieved November 7, 2014 – via Wikimedia Commons.
- "Reno City Council Learns Potential Corridors for Future Interstate 11". Retrieved September 12, 2018.
|Wikimedia Commons has media related to Interstate 580 (Nevada).|