Question: Interstate 15 and Las Vegas Boulevard run parallel to each other in which direction?
About the article "Las Vegas Strip", section "Boundaries".

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Motorists in California leave the mountainous Mojave Desert and begin a long descent through Ivanpah Valley and Ivanpah Dry Lake.
Interstate 15 crosses the Nevada state line at the first exit, Primm.
Once Interstate 15 leaves Primm, the route travels north through the desert with few services.
The highway then enters the Las Vegas urban area upon passing the State Route 146 (Saint Rose Parkway) interchange.
Quickly thereafter, the interstate meets Interstate 215, or the Southern Beltway Interchange, which provides access to Henderson and McCarran International Airport.
Originally, this interchange was termed "Son of Spaghetti Bowl" by the Las Vegas Review-Journal when the interchange was built.
Interstate 15 travels along the west side of the Las Vegas Strip corridor and just west of downtown Las Vegas just before its junction with Interstate 515 and U.S. Route 95 (the "Spaghetti Bowl" interchange).
Then the interstate enters North Las Vegas and continues to run roughly parallel to Las Vegas Boulevard (old US 91) as it leaves the Las Vegas urban limits near the northern junction with the Clark County 215 beltway.
Once Interstate 15 leaves North Las Vegas, the freeway travels northeast and crosses the Muddy River at Glendale and then climbs up onto the Mormon Mesa.
At Mesquite, the freeway then crosses the Arizona state line and cuts through the extreme northwestern corner of Arizona through the Virgin River Gorge before entering Utah. 
McCarran International Airport (LAS) provides commercial flights into the Las Vegas.
The airport serves domestic, international, and cargo flights, as well as some private aircraft.
General aviation traffic, however, will typically use the much smaller North Las Vegas Airport, or other airfields in the county.
Public transportation is provided by RTC Transit.
Numerous bus routes cover Las Vegas, Henderson, North Las Vegas, and other suburban areas.
The Las Vegas Monorail runs from the MGM Grand Hotel at the south end of the Strip to the Sahara Hotel and Casino at the north end of the Strip.
The street numbering system is divided by the following streets:  Westcliff Drive, US 95 Expressway, Fremont Street and Charleston Boulevard divide the north-south block numbers from west to east.
Las Vegas Boulevard divides the east-west streets from the Las Vegas Strip to near the Stratosphere, then Main Street becomes the dividing line from the Stratosphere to the North Las Vegas border, after which the Goldfield Street alignment officially divides east and west.
On the east side of Las Vegas, block numbers between Charleston Boulevard and Washington Avenue are different along Nellis Boulevard, which is the eastern border of the city limits.
All city street signs begin with a "N", "S", "W", or "E" designation.
Until 1997, the Amtrak Desert Wind train service ran through Las Vegas using the Union Pacific Railroad (UP) rails that run through the city; Amtrak service to Las Vegas has since been replaced by Amtrak's Thruway Motorcoach bus service.
Plans to restore Los Angeles to Las Vegas Amtrak service using a Talgo train have been discussed but no plan for a replacement has been implemented.
The Las Vegas Amtrak station was located in the Plaza Hotel.
It had the distinction of being the only train station located in a casino.
Two major freeways—Interstate 15 and Interstate 515/U.S.
Route 95—cross in downtown Las Vegas.
I-15 connects Las Vegas to the Southern California coastal urban centers of Los Angeles and San Diego, and heads northeast to and beyond Salt Lake City, Utah.
I-515 goes southeast to Henderson, beyond which US 93 continues over the Hoover Dam towards Phoenix, Arizona and the Arizona Sun Corridor.
US 95 connects the city to northwestern Nevada, including Carson City and Reno.
US 93 splits from I-15 northeast of Las Vegas and goes north through the eastern part of the state, serving Ely and Wells, and US 95 heads south from US 93 near Henderson through far eastern California.
A three-quarters beltway has been built, consisting of Interstate 215 on the south and Clark County 215 on the west and north.
Other radial routes include Blue Diamond Road (SR 160) to Pahrump and Lake Mead Boulevard (SR 147) to Lake Mead.
With the notable exceptions of Las Vegas Boulevard, Boulder Highway (SR 582), and Rancho Drive (SR 599), the majority of surface streets outside downtown Las Vegas are laid out along Public Land Survey System section lines.
Many are maintained by the Nevada Department of Transportation as state highways. 
The Boulevard leaves the city of Las Vegas at Sahara Avenue and assumes its unofficial name the "Las Vegas Strip" for the next .
This portion of Las Vegas Boulevard begins a few blocks to the north at the Stratosphere (the only major Strip hotel/casino actually sited within the Las Vegas city limits) and runs past Mandalay Bay ending at Russell Road.
This is the section of the road most people are familiar with; it is home to casino megaresorts with their world famous lights, huge video signs and other attractions.
It is designated as an All-American Road.
Just past the end of "The Strip", the road passes the Welcome to Fabulous Las Vegas sign (located in the median) as it abuts the western edge of the McCarran International Airport property.
The "South Strip" is now used to describe the section of Las Vegas Boulevard between Russell Road and Blue Diamond Road (which was recently relocated to intersect at Windmill Lane).
Along this stretch, development thins out except for newer shopping malls, hotels and condominiums as the Boulevard continues to travel south, just to the east of Interstate 15. 
  Henderson Spaghetti Bowl in Henderson (Interstate 515/U.S.
Route 93/U.S.
Route 95, Interstate 215, Lake Mead Parkway)  Las Vegas Spaghetti Bowl, where Interstate 15 and U.S. Route 95 intersect (also U.S. Route 93 and Interstate 515 being one or the other) in downtown Las Vegas, along with access to/from Martin Luther King Jr Boluevard.
Oran Grayson Freeway (U.S. Route 95,) Summerlin Parkway, and Rainbow Boulevard (NV-595) in Las Vegas.
Reno Spaghetti Bowl, the interchange between Interstate 80 and Interstate 580/U.S.
Route 395 in Reno.  
RTC Transit is a public transportation system providing bus service throughout Las Vegas, Henderson, North Las Vegas, and other suburban areas of the valley.
Inter-city bus service to Las Vegas is provided by Greyhound, many charter services, including Green Tortoise, and several Chinatown bus lines.
Though no Amtrak trains have served Las Vegas since the Desert Wind was cancelled in 1997, Amtrak California operates Thruway Motorcoach dedicated service between the City and its passenger rail stations in Bakersfield, California as well as Los Angeles Union Station via Barstow.
A bus rapid transit link in Las Vegas called the Strip & Downtown Express (previously ACE Gold Line) with limited stops and frequent service was launched in March 2010, and connects Downtown Las Vegas, the Strip, the Las Vegas Convention Center, and Town Square.
In addition, the Las Vegas Monorail connects different casinos on the Strip and with a planned extension to Las Vegas International Airport.
With some exceptions, including Las Vegas Boulevard, Boulder Highway (SR 582), and Rancho Drive (SR 599), the majority of surface streets in Las Vegas are laid out in a grid along Public Land Survey System section lines.
Many are maintained by the Nevada Department of Transportation as state highways.
The street numbering system is divided by the following streets: Westcliff Drive, US 95 Expressway, Fremont Street, and Charleston Boulevard divide the north–south block numbers from west to east.
Las Vegas Boulevard divides the east–west streets from the Las Vegas Strip to near the Stratosphere, then Main Street becomes the dividing line from the Stratosphere to the North Las Vegas border, after which the Goldfield Street alignment divides east and west.
On the east side of Las Vegas, block numbers between Charleston Boulevard and Washington Avenue are different along Nellis Boulevard, which is the eastern border of the city limits.
Interstates 15, 515, and US 95 lead out of the city in four directions.
Two major freeways – Interstate 15 and Interstate 515/U.S.
Route 95 – cross in downtown Las Vegas.
I-15 connects Las Vegas to Los Angeles, and heads northeast to and beyond Salt Lake City, Utah.
I-515 goes southeast to Henderson, beyond which US 93 continues over the Mike O'Callaghan–Pat Tillman Memorial Bridge towards Phoenix, Arizona.
US 95 connects the city to northwestern Nevada, including Carson City and Reno.
US 93 splits from I-15 northeast of Las Vegas and goes north through the eastern part of the state, serving Ely and Wells.
US 95 heads south from US 93 near Henderson through far eastern California.
A partial beltway has been built, consisting of Interstate 215 on the south and Clark County 215 on the west and north.
Other radial routes include Blue Diamond Road (SR 160) to Pahrump and Lake Mead Boulevard (SR 147) to Lake Mead.
East–west roads, north to south Ann Road  Craig Road (SR 573)  Cheyenne Avenue (SR 574) Smoke Ranch Road  Washington Avenue (SR 578) Summerlin Parkway  Bonanza Road (SR 579)  Charleston Boulevard (SR 159)  Sahara Avenue (SR 589) North–south roads, west to east Fort Apache Road Durango Drive Buffalo Drive  Rainbow Boulevard (SR 595)  Jones Boulevard (SR 596) Decatur Boulevard Valley View Boulevard  Rancho Drive Maryland Parkway  Eastern Avenue (SR 607) Pecos Road  Lamb Boulevard (SR 610)  Nellis Boulevard (SR 612) McCarran International Airport handles international and domestic flights into the Las Vegas Valley.
The airport also serves private aircraft and freight/cargo flights.
Most general aviation traffic uses the smaller North Las Vegas Airport and Henderson Executive Airport.
The Union Pacific Railroad is the only Class I railroad to provide rail freight service to the city.
Until 1997, the Amtrak Desert Wind train service ran through Las Vegas using the Union Pacific Railroad tracks.
Amtrak service to Las Vegas goes to Needles, California and continues on Amtrak's Thruway Motorcoach bus service.
Plans to restore Los Angeles to Las Vegas Amtrak service using a Talgo train were discussed in the late 1990s, but the plan was not implemented.
In November 2012 Las Vegas Railway Express announced an agreement with Union Pacific Railroad to provide passenger service from Fullerton, California to Las Vegas using the Union Pacific Railroad tracks.
Known as the "X Train", regular service is expected to start in 2014.
The Las Vegas Amtrak station was located in the Plaza Hotel; it held the distinction of being the only train station in the US that was located in a casino.