Interstate 15; the Mojave Freeway from Barstow to the Nevada State Line

Interstate 15 north of Interstate 215 near Cajon Pass towards the Nevada State Line is known as the Mojave Freeway.  From Interstate 215 north through Cajon Pass the route of Interstate 15 passes through the booming Mojave Desert communities of Hesperia and Victorville before reaching Barstow.  North of Barstow towards the Nevada State Line the route of Interstate 15 enters a sparsely inhabited 110 mile stretch of the Mojave Desert within northern San Bernardino County.   

Part 1; the development of Interstate 15 north of Barstow to the Nevada State Line

This blog focuses primarily on the events leading to the development of Interstate 15 ("I-15") north of Barstow after US Route 91 ("US 91") was extended to Long Beach in 1947.  For information pertaining to the development of US 91, US 466 and the Arrowhead Trail in northern San Bernardino County please consult the blog below:

The Vague Original Southern Terminus of US Route 91 in the Californian Mojave Desert

US 91/466 during the mid-20th Century would become a major corridor of travel as their multiplex was the primary connecting route from Las Vegas to the interior of Southern California.  In the original version of the Interstate Highway System the route of US 91/466 Barstow north to the Nevada State Line was approved as a chargeable Interstate on July 7th, 1947.  Ultimately original version the Interstate Highway System was not legislatively approved.

In the events leading to the 1956 Federal Highway Aid Act the alignment of US 91/466 north of Barstow to the Nevada State Line was retained as a planned Interstate.  This 1955 planning map shows the potential Interstate north of Barstow to the Nevada State Line as a being planned as a four-lane limited access road slated to be complete by 1965.  Ultimately the Federal Highway Aid Act was signed into law on June 29th, 1956. 

The September/October 1961 California Highways & Public Works announced the opening of the Barstow Bypass.  The Barstow Bypass was primarily a component of I-15 which opened on July 5th, 1961.  The Barstow Bypass included the exit ramp to I-40 and the first stub of the freeway eastward towards Needles.  The Barstow Bypass included a ramp north of the Mojave River from which US 466 eastbound joined US 91/I-15 northbound at what is now Exit 186/Old Highway 58.  The Barstow Bypass was an extension of a 24 mile segment of US 91/US66/I-15 which had opened to traffic north of Victorville during January of 1959.  

The September/October 1961 California Highways & Public Works also announced the opening of the Baker Grade as a full freeway alignment of US 91/US 466/I-15.  This new segment of US 91/US 466/I-15 is stated to have been 25 miles in length originating from the eastern outskirts of Baker towards Halloran Summit at Cima Road.  Previous to being upgraded to a freeway the segment of US 91/466 northeast from Baker towards Halloran Summit was known as "Bloody Baker Grade" due to the high number of accidents seen on the busy roadway.

The completed Barstow Bypass and upgraded Baker Grade can be seen on the 1962 Division of Highways State Map.  

On August 23rd, 1961 the AASHO Executive Committee Authorized the creation of US 91 Business in Barstow.  US 91 Business in Barstow followed much of it's original surface alignment on what was US 466 (now Old Highway 58), 1st Avenue and Main Street.  The US 91 Business route looped back to US 91/US 66/I-15 via ramps from Main Street which have been since replaced with the I-15 L Street Exit. 

The November/December 1963 California Highways & Public Works cited a 45 mile segment of US 91/US 466/I-15 as being the process of construction from Yermo to Cronese Valley.  US 91/US 466/I-15 is cited to have opened to freeway standards from Cima Road northeast to the Nevada State Line during October 1963.  

During the 1964 State Highway Renumbering the Legislative Route Numbers ("LRNs") were dropped from the State Highway System.  Previous to 1964 US 91/US 466/I-15 from Barstow to the Nevada State Line were part of LRN 31.  The 1964 Division of Highways State Map shows US 91/US 466 from Barstow to the Nevada State Line legislatively defined as part of Route 15.   US 91 is shown truncated from Long Beach to Barstow.  It is not clear when/if US 91 was approved for truncation by the AASHO Executive Committee.  

US 466 was approved for truncation from Morro Bay to California State Route 127 ("CA 127") in Baker by the AASHO Executive Committee during June 1964.  

The 1965 Division of Highways Map shows US 466 ending at CA 127 in Baker.  US 91/I-15 are shown completed to freeway standards from Barstow northward to the outskirts of Soda Lake.  

I-15 was announced as being completed to freeway standards north of Barstow in the September/October 1965 California Highways & Public Works.  The articles cites a 18 mile segment of recently opened freeway through Baker which relocated US 91/I-15 to a bypass of the community.  Numerous photos of the recently completed I-15 north of Barstow are shown (including the agricultural station at Yermo).  Yermo is cited to have been bypassed by a freeway realignment of US 91/US 466/I-15 which opened in 1963.  Much of the early history of US 91, LRN 31 and the Arrowhead Trail is also recapped.   

The AASHO Executive Committee approved a Division of Highways request to truncate US 91 to CA 127 in Baker on November 27th, 1966.  

US 91 can be seen truncated to CA 127 in Baker on the 1967 Division of Highways Map.  Oddly the 1967 Division of Highways Map shows no indication of US 466.   

On December 4th, 1971 US 466 was eliminated as a US Route by the AASHO Executive Committee.  This request was made by the Division of Highways in reference to the remaining segment of US 466 multiplexed with I-15 to CA 127 in Baker.   The Division of Highways request to eliminate US 466 was made in concurrence with the States of Arizona and Nevada.   

During May of 1974 Caltrans petitioned the AASHO to truncate US 91 from California.  This request by Caltrans was made alongside additional requests to truncate US 91 from Nevada and Arizona which were heard during the June 1974 AASHO Executive Committee Meeting.  This ultimately led to US 91 being truncated from CA 127 in Baker northward to Brigham City, Utah.  

Following the completion of I-15 north of Barstow to the Nevada State Line traffic using the corridor expanded rapidly alongside the growth of Las Vegas.  In time the Agricultural Station at Yermo became choke point for southbound travel on I-15 due to trucks having share the two lanes with passenger vehicles.  More so, the Agricultural Station in Yermo could easily be bypassed by freight and passenger vehicles by departing I-15 onto former US 91/466 on Yermo Road.  The Yermo Agricultural Station can be seen in this photo from the September/October 1965 California Highways & Public Works.  

During December 2018 a new Agricultural Station was opened on I-15 southbound near the Nevada State Line.   The new Agricultural Station includes expanded passenger vehicle lanes and a separate grade for freight vehicles.  The new Agricultural Station was placed south of the Yates Well Road Exit (Exit 291) which makes it virtually impossible for freight vehicles to bypass (given the only way around is via ungraded Ivanpah Road).   Following the opening of the new Agricultural Station (sometimes referred to as the Primm Agricultural Station) the Yermo Agricultural Station was demolished.  

The photos below feature a drive on I-15 southbound from Yates Well Road through the passenger of lanes of the new Agricultural Station.  

Part 2; a drive on Interstate 15 north from Barstow to the Nevada State Line

CA 58 has an eastern terminus south of Barstow which terminates at I-15.  Transitioning from CA 58 onto I-15 northbound the first Exit accessed is Exit 181 for L Street at what would have been the US 91 Business Loop.  

I-15 northbound Exit 182 in Barstow accesses CA 247/Barstow Road.  

I-15 northbound Exit 184A accesses I-40 whereas Exit 184B accesses former US 66 on Main Street in downtown Barstow.  The gantry at the split of I-15/I-40 at Exit 184A is the same one displayed in the cover photo of this blog albeit highly modernized.  

I-15 northbound crosses under the BNSF Railroad beyond Main Street and I-40.

I-15 northbound departing downtown Barstow crosses the Mojave River.

Departing Barstow I-15 northbound accesses Old Highway 58 (former US 91 and US 466) at Exit 186.  

Upon leaving Barstow I-15 northbound is signed 151 miles from Las Vegas. 

Fort Irwin is accessible from I-15 northbound Exit 189.  

I-15 northbound Exit 191 accesses Ghost Town Road.  Ghost Town Road is direct access to the Calico ghost town and County Park.  The USMC Yermo Annex Logistics Base can be accessed by way of Exit 191 on former US 91 on Daggett-Yermo Road.  

I-15 northbound Exit 194 accesses Calico Road and Yermo.  

I-15 northbound Exit 196 accesses former US 91/466 at Yermo Road.  

I-15 northbound Exit 198 accesses Minneola Road. 

I-15 northbound is signed as 140 miles from Las Vegas just beyond Minneola Road. 

I-15 northbound Exit 206 accesses Harvard Road. 

I-15 northbound Exit 213 accesses Field Road. 

I-15 northbound Exit 217 accesses a Rest Area. 

I-15 northbound Exit 221 accesses Afton Road.  

I-15 north of Afton Road is signed as 116 miles from Las Vegas.

I-15 northbound enters a series of canyons lined by volcanic rock and accesses Basin Road at Exit 230.

I-15 northbound Exit 233 accesses Rasor Road.  

I-15 northbound Exit 239 accesses the infamous Zzyzx Road.  

I-15 northbound descends towards Soda Lake and Baker.  At Exit 245 I-15 northbound accesses former US 91/466 at Baker Boulevard.   

I-15 northbound enters Baker where it accesses CA 127/Death Valley Road and Kelbaker Road at Exit 246.  CA 127 is signed as access to Death Valley National Park whereas Kelbaker Road is signed as access to the Mojave National Preserve.  Exit 246 was where US 466 began until 1971 and US 91 until 1974.  

Departing Baker I-15 northbound crosses under Baker Boulevard and is signed as 89 miles from Las Vegas.  

I-15 northbound begins to ascend and has a truck climbing lane.  I-15 northbound Exit 259 accesses Halloran Springs Road.  

I-15 northbound crosses the 4,000 elevation mark approaching Exit 265/Halloran Summit Road.  

I-15 northbound begins to descend from Halloran Summit and accesses another Rest Area at Exit 270.  

Strangely the Halloran Summit Rest Area is adorned with US 66 and National Old Trails Road displays.  While they are nice I can't help but feel (rare opinion) that displays for US 91, US 466 and the Arrowhead Trail would be far more appropriate.  

I-15 northbound Exit 272 accesses Cima Road.  Cima Road is signed as access to the Mojave National Preserve.  

I-15 north of Cima Road begins another ascent which features a climbing lane and a brake check area.  I-15 northbound peaks at 4,730 feet above sea level in the small community of Mountain Pass.  Mountain Pass can be accessed from I-15 northbound Exit 281/Bailey Road.  

I-15 northbound begins a 6% grade descent from Mountain Pass to Nipton Road at Exit 286.  

I-15 northbound continues to descend and passes by the new Agricultural Station approaching Exit 291/Yates Well Road.  Las Vegas is signed as 51 miles away on I-15 northbound approaching Yates Well Road.  

I-15 north of Yates Well Road enters the State of Nevada and Clark County.  The casino oriented community of Primm is obvious from I-15 approaching the Nevada State Line.