California 4 connects the San Francisco Bay Area with the Sierra Nevada, passing through the city of Stockton along its path. The highway begins at Interstate 80 near Hercules, and begins as a four-lane expressway from Hercules east toward Martinez. Once in Martinez, California 4 becomes a full freeway known as the California Delta Highway. Along this industrial route, California 4 serves the power plants, ports, and industries of Concord, Pittsburg, and Antioch. The freeway then connects to the California 160 high bridge that crosses over the Sacramento/San Joaquin River Delta on its journey north to Sacramento.
East of California 160, California 4 becomes a very busy two-lane highway on its way to Stockton, one of the largest cities of the Central Valley. The ride approaching Stockton can be very busy at times, since California 4 is the principal route between the Central Valley and the Delta. Although California 4 is briefly a freeway between Interstate 5 and California 99, it resumes as a busy, two-lane road as it approaches the Sierra Nevada foothills.
Passing the Gold Country Highway (California 49) in Angels Camp, California 4 begins its ascent toward Ebbetts Pass. The highway begins to lose traffic as it passes by the mountain communities of Calaveras County. After passing by California 207 (Spur route into Bear Valley Ski Area) and Lake Alpine, California 4 becomes a one and a half lane road, so traffic must slow for any oncoming traffic over Ebbetts Pass. On the rainshadow side of the Sierra Nevada, California 4 descends toward its eastern terminus at California 89 south of Markleeville and west of Monitor Pass. Some maps show California 4 continuing east into Nevada via California 89 south and California 88 east, but this is not the case based on signage present in the field.
California 4/John Muir Parkway east
Between Interstate 80 and California 160, California 4 is a four to eight-lane freeway, paralleling the Sacramento/San Joaquin River Delta south shore in Contra Costa County. A recently improved stretch of California 4 is the John Muir Parkway between Interstate 80 and the city of Martinez. This photo shows a mileage sign along eastbound after the Cummings Skyway interchange providing the distance to the cities of Martinez, Antioch, and Stockton. Photo taken 04/02/04.
Reassurance marker for California 4 along eastbound. Photo taken 04/02/04.
At the time this picture was taken, the Delta was in spring's full bloom, leaving pastoral green hills and new plant growth. However, when the temperatures approach 100 degrees in the summer, these hills will dry out, thus leaving them a golden brown color. Photo taken 04/02/04.
Mileage sign along eastbound for the next two exits: Exit 9, Alhambra Avenue and Exit 10, Pine Street/Center Avenue. Photo taken 04/02/04.
Alhambra Avenue is the first Martinez exit. Photo taken 04/02/04.
The John Muir National Historic Site, which is the location of the mansion in which John Muir lived between 1890 and his death in 1914, is located just off of Alhambra Avenue north of California 4. Photo taken 04/02/04.
Martinez, the seat of Contra Costa County, is home to 36,715 residents and is the birthplace of the martini, which was first publicized outside of Martinez in 1849. This popular alcoholic beverage is more fashionable than ever, with bars throughout the world offering assorted varieties of the drink. Photo taken 04/02/04.
Eastbound California 4 at Exit 9, Alhambra Avenue. The next exit is Exit 10, Pine Street/Center Avenue. Photo taken 04/02/04.
Mileage sign along eastbound California 4 for the next two exits: Exit 10, Pine Street/Center Avenue and Exit 11, Morello Avenue/Glacier Drive. Photo taken 04/02/04.
Eastbound California 4 at Exit 10, Pine Street/Center Avenue. Photo taken 04/02/04.
This approach sign for Exit 11, Morello Avenue/Glacier Drive, is mounted on the overpass for the Pine Street/Center Avenue interchange. Photo taken 04/02/04.
This mileage sign along eastbound provides the distance to the next three exits: Exit 11, Morello Avenue/Glacier Drive; Exit 12A, Pacheco Drive; and Exits 12B-C, Junction Interstate 680. Photo taken 04/02/04.
Eastbound California 4 reaches Exit 11, Morello Avenue/Glacier Drive. This kind of sign bridge is typically found on the older sections of Interstate 680, especially south of Walnut Creek. Photo taken 04/02/04.
Mileage sign along eastbound California 4 for the next three exits: Exit 12A, Pacheco Drive; Exits 12B-C, Junction Interstate 680; and Exit 14, Solano Way. Photo taken 07/06/06.
A second mileage sign along eastbound California 4 provides the distance to the next two cities (Concord and Pittsburg) and the control city (Stockton). California 4 departs Martinez near here and enters unincorporated Contra Costa County. It will enter Concord after the interchange with Interstate 680. Photo taken 07/06/06.
While the next exit is Exit 12A, Pacheco Drive, this sign focuses attention on the following interchange: Exits 12B-C, Junction Interstate 680. Interstate 680 is the main north-south freeway corridor through the San Ramon Valley to the south and to the Solano Lowlands to the north. As one of three routes over the Delta (the others being Interstate 80 between Rodeo and Vallejo and California 160 north of Antioch), Northbound Interstate 680 is a major route connecting to Interstate 80 en route to Sacramento, other Northern California destinations, and Nevada. Southbound Interstate 680 connects to California 24 en route to Oakland and San Francisco and also heads to San Jose. It connects to Interstate 580 as well, which leads to the Central Valley, Fresno, and Southern California. Photo taken 07/06/06.
Pacheco Boulevard leads northwest into downtown Martinez and southeast into Pacheco and Pleasant Hill. Photo taken 07/06/06.
Eastbound California 4 reaches Exit 12A, Pacheco Drive. The next exit is the cloverleaf interchange for Exits 12B-C, Junction Interstate 680. Photo taken 07/06/06.
Use Interstate 680 south to reach Walnut Creek and Pleasant Hill. Photo taken 07/06/06.
Eastbound California 4 reaches Exit 12B, Junction Interstate 680 south. This is a cloverleaf interchange, so watch for merging traffic from the right, followed by the loop ramp to northbound Interstate 680. As part of a reconstruction of the Interstate 680 corridor from California 242 north to Interstate 780 (including the Benicia-Martinez Bridge), this interchange was reconfigured into a modified cloverleaf interchange for Interstate 680. Photo taken 07/06/06.
A loop ramp connects eastbound California 4 onto Interstate 680 north to Martinez, Benicia, and Interstate 80 at Fairfield. These signs were replaced in 2004. From here, California 4 shifts from the John Muir Parkway to the California Delta Highway. A notable change in topography occurs as there are fewer trees and more wide open spaces. Photo taken 07/06/06.
California 4/California Delta Highway (Arnold Industrial Highway) east
A California 4 east reassurance shield assembly is posted after the Interstate 680 interchange as the freeway crosses over Grayson Creek. Photo taken 07/06/06.
California 4 was named the California Delta Highway since it parallels the Carquinez Strait and Suisun Bay, then enters the California Delta Region formed by the confluence of the Sacramento River from the north and the San Joaquin River from the south. Photo taken 07/06/06.
The next exit along eastbound California 4/California Delta Highway is Exit 13, Arnold Industrial Place to Solano Way and Olivera Road. Photo taken 07/06/06.
Exit 13 is the first of three to serve the city of Concord, which is the largest city in Contra Costa County (but is not the county seat). Home to 121,780 people as of the 2000 Census, Concord contains 31.31 square miles and was incorporated as a town in February 1905. Solano Way travels southeast toward downtown Concord, while Olivera Road travels east past Hillcrest Community Park, then turns southeast to meet Willow Pass Road near Willow Pass Community Park. Photo taken 07/06/06.
Eastbound California 4/California Delta Highway reaches Exit 13, Arnold Industrial Place to Solano Way and Olivera Road. The next exit along California 4 east is Exit 15A, Junction California 242 south. Photo taken 07/06/06.
The right lane of California 4/California Delta Highway east becomes exit only for Exit 15A, Junction California 242 south to downtown Concord and Pleasant Hill. The control city of Oakland dates back to the original designation of Califronia 242 as an extension of California 24, but that designation changed in the late 1980s or early 1990s. Several California 242 overhead guide signs have a green overlay panel as a result of this relatively recent change (since California's overhead signs generally are made to last for a long time and thus are not replaced for decades). Photo taken 07/06/06.
Exit 15B, the second exit after the California 242 split, connects to Port Chicago Highway. This exit connects to the U.S. Naval Weapons Station at Concord and the unincorporated community of Clyde, which is located north of Concord and south of the Military Ocean Terminal at Concord. Photo taken 07/06/06.
Eastbound California 4/California Delta Highway reaches Exit 15A, Junction California 242 south to downtown Concord and Pleasant Hill. The next exit is Exit 15B, Port Chicago Highway to Clyde and the naval weapons station. Photo taken 07/06/06.
An exit number for Exit 15A, Junction California 242 south is posted. The offramp to Exit 15B can be seen in the distance. Photo taken 07/06/06.
After traffic merges from California 242 north onto California 4 east, the California Delta Highway widens to four lanes. The exit ramps to Port Chicago Highway (Exit 15B) can be seen on the collector-distributor lanes. Photo taken 07/06/06.
Continuing east, the exit ramp to Port Chicago Highway can be seen from the main lanes of California 4 east. The first ramp on the collector-distributor lanes connects to Port Chicago Highway south to downtown Concord along an alignment that roughly parallels the California 242 freeway. Photo taken 07/06/06.
The collector-distributor lanes meet the ramp to Port Chicago Highway north to the Diablo Creek Golf Course, U.S. Naval Weapons Station - Concord, and Military Ocean Terminal - Concord. The collector-distributor lanes then prepare to merge back onto the main lanes of California 4 east. Behind the California 4/Port Chicago Highway split sign, note the Bay Area Rapid Transit (BART) train making its way southwest into Concord. From here east to Pittsburg, the BART will closely follow California 4 east. Photo taken 07/06/06.
Climbing up toward Willow Pass, the next exit on California 4 east is Exit 17, Willow Pass Road southwest to Concord. Much of this land is undeveloped due to its location within the U.S. Naval Weapons Station - Concord. However, with recent base closures, the future of this site is unknown. Photo taken 07/06/06.
This mileage sign provides the distance to Pittsburg (eight miles), Antioch (13 miles), and Stockton (52 miles). The next three exits serve the unincorporated community of Bay Point, which is located north of California 4 and generally west of the city of Pittsburg. Photo taken 07/06/06.
The next three exits on California 4 east are Exit 17, Willow Pass Road; Exit 19, Bay Point; and Exits 20A-B, Bailey Road south and north. Photo taken 07/06/06.
Eastbound California 4 reaches Exit 17, Willow Pass Road. Use Willow Pass Road southwest to Concord and north to Evora Road, which travels east into Bay Point. Photo taken 07/06/06.
Upon exiting at Willow Pass Road, an auxiliary sign advises that a left turn is needed to connect to east-west Evora Road, and a right turn is needed to get to Avila Road east to the Concord Police Academy. Photo taken 07/06/06.
California 4 east between Antioch and Stockton
Eastbound California 4 meets Byron Highway at this intersection. Photo taken 01/18/03.
In the Delta region, California 4 crosses a variety of bridges over the various waterways that cross the region. Here, eastbound California 4 uses the Old River Bridge to cross one of these channels. Photo taken 01/18/03.
Soon thereafter, eastbound California 4 crosses another channel at the Middle River Bridge. Photo taken 01/18/03.
Eastbound California 4 approaches Junction San Joaquin County Route J2, Tracy Boulevard. First two photos taken by Joel Windmiller, 08/01; third photo taken 01/18/03.
Eastbound California 4 crossing the San Joaquin River just east of Byron. Along with the Sacramento River, the San Joaquin River forms the California Delta. Photo taken 01/18/03.
Eastbound California 4 entering the city of Stockton. Photo taken 01/18/03.
Eastbound California 4 approaching Junction Interstate 5, one mile, in Stockton. The Crosstown Freeway westerly extension, once constructed, would meet existing California somewhere near this location. Currently, traffic must follow California 4 to Interstate 5, turn north briefly on the Interstate, then turn east again on the Crosstown Freeway. Another alternative is to take Fresno Avenue northbound to the current western terminus of the Crosstown Freeway, which is located a half-mile west of the Interstate 5 interchange. Photo taken 01/18/03.
Eastbound California 4 Stockton Crosstown Freeway
Northbound Fresno Avenue approaching Junction Eastbound California 4, the Crosstown Freeway. This freeway is proposed to be extended west from here to meet existing California 4, but it has not yet been constructed. Photo taken 01/18/03.
Eastbound California 4 reaches Exits 65A-B, Junction Interstate 5. The California 4 designation for this freeway begins after the interchange. Use south Interstate 5 to reach west California 4. Photo taken 01/18/03.
View of the symmetrical stack interchange along Eastbound California 4 for Interstate 5 as it approaches Exit 65C, the downtown Stockton exit. Photo taken 01/18/03.
The next exit along eastbound California 4 is Exit 65C, the downtown Stockton exit. Photo taken 01/18/03.
Following that, eastbound California 4 reaches Exit 66, Stanislaus Street, which also leads into downtown Stockton. Photo taken 01/18/03.
The Crosstown Freeway follows eastbound California 4 to Exit 67, Wilson Way. Photo taken 01/18/03.
This freeway entrance shield assembly for California 4 is for westbound in Stockton. Photo taken by Pete Sison, 07/01.
Eastbound California 4 freeway at Exit 68A, Filbert Street, approaching Junction California 99 in Stockton. The connection from California 4 to California 99 was built in the early 1990s and was open by the late 1990s. At this time, the Stockton East-West Freeway does not extend any further south than California 99. First photo taken by Pete Sison, 07/01; second photo taken 01/18/03.
After California 99, California 4 returns to a two-lane highway on its journey toward Angels Camp and Ebbetts Pass over the Sierra Nevada Mountains. This picture was taken along eastbound California 4 as it approaches Junction California 99. First photo taken by Pete Sison, 07/01; second photo taken 01/18/03.
Eastbound California 4 at Junction California 99 in Stockton. California 4 merges onto southbound California 99 briefly, then heads east on a two-lane highway. First photo taken by Pete Sison, 07/01; second two photos taken 01/18/03.
Eastbound California 4 through the Foothills and Sierra Nevada
Eastbound California 4 at Junction San Joaquin County Route J-6 in Farmington. Photo taken 01/18/03.
This mileage sign along California 4 east is posted upon leaving Farmington. First photo taken by Trevor Carrier, Summer 2002; second photo taken 01/18/03.
California 4 enters Stanislaus County. Photo taken 01/18/03.
Continuing east, California 4 meets Stanislaus County Route J-14/Milton Road at this intersection. This road leads north to Milton, at the intersection of Calaveras County Route E-15 and Calaveras County Route J-14, and ultimately to Junction California 26 near Jenny Lind. Photo taken 01/18/03.
Eastbound California 4 approaches Junction Calaveras County Route E-15, O'Byrnes Ferry Road. The county shield was omitted from the advance signage, and the only county route shield still in place seems to be just north of the Tuolumne-Calaveras County Line. Photo taken 01/18/03.
Meeting Calaveras County Route E-15/O'Byrnes Ferry Road, California 4 continues to climb into the foothills. Calaveras County Route E-15 leads south to connect with California 108 and 120 near Chinese Camp via Tulloch Reservoir. County Route E-15 is the best route to Jamestown and Sonora from eastbound California 4. Photo taken 01/18/03.
View of eastbound California 4 as it passes through the foothills on a late winter's evening. The fog dissipates as the road slowly rises higher in elevation. Photo taken 01/18/03.
Eastbound California 4 approaches Junction California 49 in Angels Camp. First photo taken by Trevor Carrier, Summer 2002; second photo taken 01/18/03.
During the winter, Ebbetts Pass is closed, and advisory signs such as this one are placed along eastbound to warn motorists. Photo taken 01/18/03.
This eastbound California 4 mileage sign shows the distance to Murphys, a small Sierra foothill community. Big Trees State Park, a few miles further along California 4, features tall redwood trees. Markleeville is located on the east side of Ebbetts Pass, but it is not accessible via California 4 during the winter since the highway is closed over the pass. Photo taken 01/18/03.
Eastbound California 4 meets Calaveras County Route E-18 at this intersection. Calaveras County Route E-18 enters Tuolumne County, then travels south toward Columbia and Sonora. Photo taken 01/18/03.
California 4 crosses over the Sierra Nevada Mountains at Ebbetts Pass. This picture, taken in the foothills along eastbound, indicates that the highway over the pass is open. During the winter and in times of high snowfall, this pass is closed. Photo taken by Joel Windmiller (08/01).
Climbing the Sierra Nevada, California 4 crosses Ebbetts Pass. Through the top of the pass (which is closed in winter), this photo shows the "lane-and-a-half" width of the highway at this point -- the road feels like a narrow national park road in this section, given the slow speed, tight corners, and the extremely close proximity of the natural features (in particular the shores of a couple of alpine lakes). Photo taken by Glenn Pillsbury (08/21/05).
After crossing the Sierra Nevada and descending from Ebbetts Pass, eastbound California 4 approaches its end at Junction California 89 south of Markleeville. To continue east, follow California 89 north (straight ahead) to California 88. California 88 provides the connection into Carson Valley in Nevada, ultimately ending at U.S. 395 south of Carson City. Photo taken by Glenn Pillsbury (08/21/05).
Westbound California 4: California Delta Highway
After transitioning from the California 160/Antioch Bridge interchange, the first exit along westbound California 4 is Exit 29, Hillcrest Avenue, one mile. Photo taken 01/18/03.
Westbound California 4 reaches Exit 29, Hillcrest Avenue in Antioch. Photo taken 01/18/03.
Westbound California 4 reaches Exit 28, A Street/Lone Tree Avenue in Antioch. Photo taken 01/18/03.
The vintage guardrail on the highway overpass will likely be removed when California 4 is widened to accommodate an increasing east-west traffic flow through the California Delta region. This bridge also supports the one and one-quarter mile advance sign for Exit 26, Somersville Road. Photo taken 01/18/03.
This mileage sign provides the distance to Pittsburg, Martinez, and Oakland along westbound California 4. The sign is located after Exit 28 and before Exit 26, Somersville Road. Photo taken 01/18/03.
Another mileage sign is posted thereafter for next three exits along westbound California 4: Exit 26, Somersville Road; Exit 24, Loveridge Road; and Exit 23, Railroad Avenue/Harbor Street. Photo taken 01/18/03.
Westbound California 4 at Exit 26, Somersville Road. Photo taken 01/18/03.
The next exit along westbound California 4 is Exit 24, Loveridge Road, one and one-quarter miles. The next exits after Loveridge Road are Railroad Avenue and Bailey Road. Photo taken 01/18/03.
California 4 enters the city of Pittsburg. Photo taken 01/18/03.
Westbound California 4 reaches Exit 24, Loveridge Road. Note the lack of an exit sign at this exit; perhaps one used to be affixed to the overcrossing. Photo taken 01/18/03.
This California 4 west shield is found after Exit 24 and before Exit 23, Harbor Street/Railroad Avenue. Photo taken 01/18/03.
Westbound California 4 reaches Exit 23, Harbor Street/Railroad Avenue. Photo taken 01/18/03.
Westbound California 4 makes a startling transition from a four-lane to eight-lane freeway as it leaves Pittsburg. (However this area is under construction from freeway widening and extension as of 2007.) The remaining sections of four-lane freeway are inadequate to handle traffic volumes, so it is being widened, as evidenced by this bridge replacement. Photo taken 01/18/03.
This portion of westbound California 4 parallels a large power transmission line, which takes power from the plants along the Sacramento River west into the Bay Area. The first photo shows the huge quantity of power lines that emanate from this area, transmitting power all over the East Bay. Photo taken 01/18/03.
The next exit along westbound California 4 is Exits 20A-B, Bailey Avenue, one mile. Surprisingly, much of the land here is undeveloped as the freeway leaves Pittsburg/Bay Point en route to Concord. Photo taken 01/18/03.
The large transmission power lines that paralleled westbound California 4 turn off as the freeway approaches Exits 20A-B, Bailey Avenue. Photo taken 01/18/03.
Continuing west, California 4 approaches Exits 20A-B, Bailey Avenue. Photo taken 01/18/03.
Westbound California 4 reaches Exit 20B, Northbound Bailey Avenue. Photo taken 01/18/03.
Westbound California 4 reaches Exit 20A, Southbound Bailey Avenue. Photo taken 01/18/03.
The next exit along westbound California 4 is Exit 19, Bay Point, one-half mile. The median of the freeway now accommodates the Bay Area Rapid Transit (BART) train, which leads west from Bay Point to San Francisco via Concord, Walnut Creek, Orinda, and Oakland. Photo taken 01/18/03.
Westbound California 4 reaches Exit 19, Bay Point. Check out the BART train in the median. Photo taken 01/18/03.
The next exit along westbound California 4 is Exit 15B, Port Chicago Highway. Exit 15B is Junction California 242, a freeway connector between California 4 and Interstate 680. Photo taken 01/18/03.
Westbound California 4 reaches Exit 15B, Port Chicago Highway. The next exit is California 242, which is a three-lane exit and is the fastest route to westbound California 24 and Oakland. Photo taken 01/18/03.
Westbound California 4 reaches Exit 15A, Junction Westbound California 242 to Concord and Walnut Creek. Historically, this split marked where former California 24 turned southwest toward Oakland via California 242, Interstate 680, and the current California 24 freeway. To reduce route duplication and overlap, California 24 was reduced to its current alignment, and this short stretch was renumbered as California 242. Photo taken 01/18/03.
The next exit along westbound California 4 is Exits 12C-B, Junction Interstate 680. Even though this interchange connects two major freeways, it is only a cloverleaf, so it faces delays during heavy traffic periods. Photo taken 01/18/03.
Westbound California 4 reaches Exit 12C, Junction Northbound Interstate 680. Note the substandard signage marking this cloverleaf interchange, which is more suitable for a collector/distributor ramp or a surface street. Photo taken 01/18/03.
Westbound California 4 reaches Exit 12B, Junction Southbound Interstate 680. California 242 acts as the major connector between westbound California 4 and southbound Interstate 680 (rather than Exit 12B). Photo taken 01/18/03.
Westbound California 4 reaches Exit 12A, Pacheco. Photo taken 01/18/03.
The next exit along westbound California 4 is Exit 11, Morello Avenue, three-quarters of a mile. Photo taken 01/18/03.
Continuing west, California 4 approaches Exit 11, Morello Avenue, one-half mile. Photo taken 01/18/03.
Westbound California 4 reaches Exit 11, Morello Avenue. Photo taken 01/18/03.
The next exit along westbound California 4 is Exit 10, Pine Street/Center Avenue, one-half mile. Photo taken 01/18/03.
Westbound California 4 reaches Exit 10, Pine Street/Center Avenue. Photo taken 01/18/03.
The next exit along westbound California 4 is Exit 9, Alhambra Avenue in Martinez. Photo taken 01/18/03.
Westbound California 4 reaches Exit 9, Alhambra Avenue in Martinez. Photo taken 01/18/03.
This section of westbound California 4 passes through some rolling hills as it reaches the mouth of the Sacramento River, which flows into San Francisco Bay. On this day, the fog was thick enough to preclude much picture taking until nearly reaching Interstate 80. Even though much of this road is controlled access, there are a couple of connecting roads that prevent this segment of California 4 from being a full freeway. Photo taken 01/18/03.
Westbound California 4 at Exit 3, Franklin Canyon. The next exit is Exit 1C, Willow Avenue/Bayberry Avenue. Photo taken 01/18/03.
The next exit along westbound California 4 is Exit 1C, Willow Avenue/Bayberry Avenue. Photo taken 01/18/03.
Westbound California 4 reaches Exit 1C, Willow Avenue/Bayberry Avenue. The next exits are for Interstate 80 (Exit 1B) and San Pablo Avenue (Exit 1A). Photo taken 01/18/03.
The next exit along westbound California 4 is Exit 1B, Junction Interstate 80. The freeway continues straight ahead to end at San Pablo Avenue (Exit 1A). Photo taken 01/18/03.
This is a view of the signage on the offramp for Exit 1B as seen from westbound California 4. Photo taken 01/18/03.
And a bit further is this view of the partial symmetrical stack interchange between westbound California 4 and Interstate 80. Photo taken 01/18/03.
Finally, westbound California 4 ends at its junction with Historic U.S. 40 (San Pablo Avenue) in Hercules. There is no END shield assembly present at this intersection. Photo taken 01/18/03.
