Interstate 780 is a short freeway route connecting Interstate 80 in Vallejo with Interstate 680 in Benicia. Until 1976, it was signed as part of Interstate 680. In that year, Interstate 680 was transferred to the old California 21 alignment from Benicia north to Fairfield, and Interstate 780 was created along old Interstate 680 from Benicia to Vallejo.
Interstate 780 east
Leaving Vallejo on eastbound Curtola Parkway (former California 141), the parkway changes into a freeway configuration after passing the Lemon Street traffic signal. The first interchange is a cloverleaf with Interstate 80. The first ramp connects Interstate 780 east (south) with Interstate 80 west (south) to the Alfred Zampa (Carquinez) Bridge, Richmond, Oakland, and San Francisco. The next exit is Exit 1B, Junction Interstate 80 east (north) to north Vallejo, Fairfield, and Sacramento. Note the use of a butterfly gantry sign bridge with porcelain signs that likely date to the late 1960s. Photo taken 11/26/04.
Passing under the mainline of Interstate 80, the next ramp connects Interstate 780 east with Interstate 80 east via a loop ramp. Photo taken 11/26/04.
The next exit along eastbound Interstate 780 is Exit 1C, Laurel Street north to Steffan Street and south to Magazine Street in Vallejo. Photo taken 11/26/04.
After the on-ramp from Laurel Street, this Interstate 780 east shield assembly is posted on the mainline. Most of Interstate 780 carries only two lanes in each direction. Photo taken 11/26/04.
A pedestrian bridge spans Interstate 780 as the freeway approaches Exit 1D, Glen Cove Road. Photo taken 11/26/04.
Eastbound Interstate 780 reaches Exit 1D, Glen Cove Road. An exit number sign greets us at this offramp. This interchange is a diamond interchange, the first of its kind along eastbound. Photo taken 11/26/04.
After the Glen Cove Road interchange, Interstate 780 swings a bit to the southeast. While the freeway generally remains in Vallejo, it also enters some unincorporated areas before it finally enters Benicia. Photo taken 11/26/04.
This mileage sign provides the distance to Benicia (three miles) and the Interstate 680 south control city of San Jose (61 miles). Photo taken 11/26/04.
The next exit along eastbound Interstate 780 is Exit 3A, Columbus Parkway. This interchange also connects to Rose Drive and is located within Benicia State Recreation Area. Photo taken 11/26/04.
Use Exit 3A to Benicia State Recreation Area, which is signed here as a state park. Hikers, RV campers, and fishermen enjoy this park, with its view of the Carquinez Strait. Photo taken 11/26/04.
Eastbound Interstate 780 reaches Exit 3A, Columbus Parkway/Rose Drive to Benicia State Recreation Area. Photo taken 11/26/04.
The next four exits along eastbound Interstate 780 all serve the city of Benicia: Exit 3B, Military West; Exit 4, Southampton Road; Exit 5, East Second Street; and Exit 6, East Fifth Street. Upon entering the state recreation area, Interstate 780 leaves Vallejo and enters Benicia, which is home to 26,865 people as of the 2000 Census and was founded on May 19, 1847. The city briefly served as the capital of the state of California, from February 11, 1853 through February 25, 1854 until the capital was permanently moved to Sacramento. Photo taken 11/26/04.
For the Benicia industrial park, use Interstate 780 east to Interstate 680 north to Exit 58B, Bayshore Road. A new flyover ramp makes this connection easy for trucks and other cargo haulers. Photo taken 11/26/04.
Eastbound Interstate 780 reaches Exit 3B, Military West and K Street. This is the beginning of the main business route into Benicia, with the return to the freeway at Exit 6, East Fifth Street. Photo taken 11/26/04.
An Interstate 780 east reassurance shield is posted shortly after the onramp from Southampton Road/Military West. Photo taken 11/26/04.
Eastbound Interstate 780 reaches Exit 4, Southampton Road/West Seventh Street. Southampton Road parallels Interstate 780 on the north side of the freeway between Exits 3B and 4. Photo taken 11/26/04.
The next exit along eastbound Interstate 780 is Exit 5, East Second Street to downtown Benicia. Photo taken 11/26/04.
Eastbound Interstate 780 reaches Exit 5, East Second Street to downtown Benicia, including the old Benicia Capitol building, Municipal Pier, Turnbull Park, and Benicia Marina. Photo taken 11/26/04.
The penultimate exit on Interstate 780 east is Exit 6, East Fifth Street in Benicia. Use this exit to the Benicia Arsenal The next exit is the eastern terminus of Interstate 780 at the interchange with Interstate 680 at the northern end of the Benicia-Martinez Bridge over Suisun Bay. Photo taken 11/26/04.
Eastbound Interstate 780 reaches Exit 6, East Fifth Street in Benicia. On the overhead signage, note that the northbound Interstate 680 shield (left exit) is green and was placed over a California 21 shield that was scraped off. More signs like this one used to found all along Interstate 680 through Contra Costa County, but they were completely removed with the reconstruction of the route between Concord and Dublin. Photo taken 11/26/04.
After the East Fifth Street interchange, Interstate 780 prepares to interchange with Interstate 680. The left two lanes connect to Interstate 680 south to Martinez, Concord, and Walnut Creek. The right lane connects to the Benicia Industrial Park, Fairfield, and Sacramento. Photo taken 11/26/04.
Interstate 780 ends as the freeway splits. The right lane connects to Interstate 680 north, and the left two lanes connect to Interstate 680/Benicia-Martinez Bridge south to Martinez and San Jose. There is no END Interstate 780 shield assembly. Photo taken 11/26/04.
After Exit 7A departs, the remaining through lanes of Interstate 780 are defaulted onto Interstate 680 south. The ramp to Interstate 680 north crosses over the main lanes, and this image shows the remains of the original ramp from Interstate 780 east to Interstate 680 north. This connection made it difficult for trucks to merge over to the Benicia Industrial Park interchange (Exit 58B, Bayshore Road). Photo taken 11/26/04.
The two left lanes of Interstate 780 become the two right lanes of Interstate 680 south on the Benicia-Martinez Bridge. The old toll booth, which is no longer in use, comes into view as the two freeways merge together. There is no toll on Interstate 680 south over the Carquinez Strait/Suisun Bay. The original Benicia-Martinez Bridge was opened to traffic on September 15, 1962 (George Miller, Jr. Bridge, deck truss span, 1.2 miles); the new span opened on August 25, 2007 (segmented concrete span, George Miller III Bridge, 1.7 miles). A Union Pacific railroad lift bridge sits between the two spans; it was built in 1929-1930. As part of a project to expand the Benicia-Martinez Bridge to include a new northbound span, this picture shows the massive bridge deck being installed. Pillars for the new bridge were being placed at the time this photo was taken. Upon completion, Interstate 680 over the delta was brought up to Interstate standards, including full shoulders. Photo taken 11/26/04.
Interstate 780 west
Now traveling west, the first exit along Interstate 780 west after the interchange with Interstate 680 is Exit 6, East Fifth Street in Benicia. Photo taken 12/30/01.
Westbound Interstate 780 reaches Exit 6, East Fifth Street in Benicia. The next exit is Exit 5, East Second Street. Photo taken 12/30/01.
Quickly thereafter, Interstate 780 west meets East Second Street at Exit 5 in Benicia. The next exit is for Southampton Road. Photo taken 12/30/01.
Skipping ahead a bit, westbound Interstate 780 reaches Exit 1B, Junction Interstate 80 east. This next ramp connects to Exit 1A, Junction Interstate 80 west. Photo taken 12/30/01.
As part of the cloverleaf interchange, Interstate 780 west connects with Interstate 80 west at Exit 1A. It is suprising to see a cloverleaf interchange here since it connects two Interstate highways. This marks the western terminus of Interstate 780. Photo taken 12/30/01.
After the junction with Interstate 80 in Vallejo, Interstate 780 ends and Curtola Parkway continues (former California 141). The freeway ends at this traffic light with Lemon Avenue; the road continues straight ahead as Curtola Parkway, which leads west to meet California 29 (Sonoma Boulevard). Beyoond California 29, the roadway continues as Mare Island Way and Wilson Avenue to connect to the ferry docks, Vallejo marina, Mare Island (a former naval facility), and finally Junction California 37 (Sears Point). Photo taken 11/26/04.
Scenes Pertaining to Interstate 780
This Interstate 780-80 trailblazer shield assembly is located on westbound Lemon Street at Curtola Parkway in an unincorporated area mostly surrounded by Vallejo in the immediate vicinity of the Interstate 80-780 cloverleaf interchange. Photo taken 11/26/04.
Signage for eastbound Interstate 780 as seen from East Main Street in Benicia (Exit 6). Note that Interstate 780 leads to both Sacramento and San Jose according to the guide sign, which is due to the fact that Interstate 780 terminates at Interstate 680 a mile or so east of here. Photo taken 12/30/01.
Freeway entrance assembly for westbound Interstate 780 as seen from East Main Street in Benicia (Exit 6). Although many of the mainline shields for Interstate 780 are narrow, most of the freeway entrance shields (such as these) have normal specifications for a three-digit Interstate shield. Photos taken 12/30/01.
First shield along westbound Interstate 780 after the split from northbound Interstate 680. Photo taken 12/30/01.
