File:Interstate 515, Las Vegas, Nevada (15831138737).jpg

Interstate 515 (I-515) is a spur of Interstate 15 in Nevada that runs from the junction of I-15, US 93 and US 95 (the Las Vegas Spaghetti Bowl Interchange) near downtown approximately 20 miles (32 km) southeast to just north of Railroad Pass in southeastern Henderson. I-515 exists concurrently with U.S. Routes 93 and 95 along its entire length.

The freeway, which began construction in 1982, is a continuation of the Oran K. Gragson Freeway (named for the former Las Vegas mayor who advocated for the construction of the then Las Vegas Expressway) which ran primarily along the former West Fremont Street alignment between Las Vegas Boulevard and Rainbow Boulevard. The spur was completed southeast to Charleston Boulevard (SR 159) in 1984, to Tropicana Avenue (SR 593) by 1986, to Russell Road by 1988 and to Lake Mead Parkway (SR 564), at the time known as Lake Mead Drive (SR 146 west and SR 147 east), by 1990. By 1994, the entire freeway was completed to Boulder Highway, just south of Wagon Wheel Drive. The I-515 designation was first approved by the American Association of State Highway and Transportation Officials (AASHTO) on July 12, 1976, from the I-15 interchange to the junction of US 93 and US 95 (at Boulder Highway, current exit 70).

On December 7, 1984, AASHTO approved the southeasterly extension of the route to its current terminus near Boulder City. Even though the route number was approved prior to the highway's construction, I-515 was not consistently signed until after the freeway was completed down to its current southern terminus north of Railroad Pass in 1994. Prior to the completion of the freeway, US 93 and US 95 originally followed Fremont Street / Boulder Highway from downtown Las Vegas southeast through Henderson towards to Boulder City. Boulder Highway was signed as a business route of US 93/95 after the freeway was completed, but that designation has since been removed; it is now just State Route 582. Despite being designated and signed for several years, most Las Vegas residents refer to the I-515 freeway as "US 95". This is due to the continuation of US 95 as a separate freeway west and north of I-15 (I-515 ends at I-15, while US 93 joins I-15) and also because this Interstate uses US 95 milepost and exit numbers rather than its own unique ones.

It is speculated that the I-515 designation could be extended south around Boulder City along the future US 93/Boulder City Bypass. There is also the speculation this freeway could become part of a proposed Interstate 11 to Phoenix (indeed, Phoenix is the first control city on southbound I-515's pull-through sign at exit 75B, and reflects the concurrent signing as US 93 and US 95).

en.wikipedia.org/wiki/Interstate_515