Castro Valley to Fontana is 402.1 miles and takes about 7h 26m via Westside Freeway and I 5 Truck, with a fuel budget near $91 and enough daylight to finish in a day. This drive connects the Pacific Coast regions of California, taking you from the East Bay down to the Inland Empire. It's a predominantly highway route, making it a straightforward option for a single-day trip. Plan for a solid block of driving time, as most of the mileage is on major freeways. Consider this route if you prioritize efficient travel between these two parts of the state.
Trip Pace
Same-day drive is realistic
A same-day return is possible, but it will make for a full day on the road.
Break Rhythm
2 planned breaks
Plan on a short reset every 3 to 4 hours to stay fresh behind the wheel.
Midpoint
201 miles from Castro Valley, CA
A natural place for your longest stop of the day
, about 3h 38m into the drive
.
Main Roads
Road
Distance
Duration
Westside Freeway
224.4 mi
4h
Foothill Freeway
67 mi
1h 17m
I 5 Truck
58.4 mi
1h 6m
Arthur H. Breed Junior Freeway
29 mi
33m
William Elton Brown Freeway
17 mi
18m
Sierra Avenue
3 mi
4m
Golden State Freeway
2 mi
2m
Castro Valley Boulevard
0.3 mi
<1m
Longest stretch:
Westside Freeway
— 224.4 mi, about 4h
Traffic on I-5
Hour-of-day weekday pattern from 81 FHWA count stations on your route.
Peak
2 PM
~1,500 veh/hr typical
· worst 2,272
Quietest
2 AM
~312 veh/hr
Peak-to-quiet ratio
4.8×
busier at peak than in the quiet hours
12a6anoon6p11p
Averaged across 44 weeks of 2023 FHWA Travel Monitoring Analysis System data. Weekday hours only (Mon–Fri).
Turn-by-Turn Driving Directions
Step-by-step road directions between Castro Valley, CA and Fontana, CA.
1
Start on Lake Chabot Road
60 ft·4 sec·Lake Chabot Road
2
Turn left onto Castro Valley Boulevard
0.3 mi·34 sec·Castro Valley Boulevard
3
Turn left onto Strobridge Avenue
0.2 mi·21 sec·Strobridge Avenue
Use the straight lane.
4
Take the ramp
0.3 mi·44 sec
Toward I 580 East
5
Merge onto I 580
11 mi·12 min·Arthur H. Breed Junior Freeway
Use the straight / slight right lanes.
6
Keep slight right at fork onto I 580
18 mi·20 min·Arthur H. Breed Junior Freeway
Use the straight / slight right lanes.
7
Keep slight right at fork onto I 580
11 mi·11 min·William Elton Brown Freeway
8
Keep slight left at fork onto I 580
5.9 mi·6 min·William Elton Brown Freeway
9
Merge onto I 5
224 mi·4 hr·Westside Freeway
Use the straight / slight right lanes.
10
Keep slight right at fork onto I 5 Truck
58 mi·1 hr 6 min·I 5 Truck
Use the straight / slight right lanes.
11
Keep slight left at fork onto I 5
2.0 mi·2 min·Golden State Freeway
Use the straight / slight right lanes.
12
Take the exit
0.3 mi·17 sec
Exit 161AToward I 210 East: PasadenaUse the slight right lane.
13
Continue on I 210
24 mi·28 min·Foothill Freeway
Use the straight / slight right lanes.
14
Keep slight right at fork onto I 210
19 mi·22 min·Foothill Freeway
Toward CA 134 West, I 210 East: San Bernardino, VenturaUse the slight right lane.
15
Keep slight right at fork onto I 210
2.9 mi·3 min·Foothill Freeway
Use the straight / slight right lanes.
16
Keep slight right at fork onto CA 210
1.4 mi·1 min·Foothill Freeway
Use the straight / slight right lanes.
17
Keep slight right at fork onto CA 210
1.2 mi·1 min·Foothill Freeway
Use the straight / slight right lanes.
18
Keep slight right at fork onto CA 210
1.8 mi·2 min·Foothill Freeway
Use the straight / slight right lanes.
19
Keep slight right at fork onto CA 210
16 mi·18 min·Foothill Freeway
Use the straight / slight right lanes.
20
Take the exit
0.3 mi·46 sec
Exit 67Toward Sierra AvenueUse the straight / slight right lanes.
21
Turn right onto Sierra Avenue
3.0 mi·4 min·Sierra Avenue
Use the left / right lanes.
22
Turn left onto Merrill Avenue
205 ft·4 sec·Merrill Avenue
Use the left lane.
23
Arrive at destination
Merrill Avenue
Trip Plan
Given the 7h 26m estimated drive time, leaving Castro Valley early in the morning is your best bet to avoid the worst traffic, especially if you're traveling on a weekday. With only two recommended stops, you can easily complete this in one day. The longest stretch without a break is over 200 miles, so be sure to fuel up before you hit that segment. Keep an eye on your fuel gauge; with a $91 estimated cost, planning your fill-ups around that budget will be practical. Consider a mid-drive stop around the halfway point to stretch your legs.
Morning Departure
Start early — leave by 6-7 AM to arrive at a reasonable hour.
Evening Departure
This is a long drive — plan for a morning departure or consider splitting it into two days.
You can normally do this drive in one day.
Plan roughly 2 meaningful breaks for fuel, food, and rest.
The halfway point lands around 201 miles from Castro Valley, CA, or about 3h 38m into the drive.
The longest continuous stretch on this route runs about 224.4 miles.
This is a comfortable same-day trip.
Departure
Before you leave
Start with fuel, water, and navigation already sorted so the first hour feels easy.
First stop
Around 88 miles or 1h 37m in
Use this first pause for coffee, a restroom break, and a quick traffic check ahead.
Halfway reset
Around 201 miles or 3h 38m in
This is the best place for your longest stop, a real meal, and a full fuel check.
Final approach
Final hour starts around 6h 15m
Traffic, exits, and arrival timing usually matter more near Fontana, CA than in the middle of the route.
Before You Leave
+
Open the route before leaving Castro Valley, CA so your first major turns are already loaded.
+
Leave with enough water and a charging cable within reach, not packed away.
+
Check your fuel range against the first long segment, especially if you are starting outside city service areas.
+
Pick one backup stop option before the midpoint in case traffic changes your pacing.
Day 1
Settle into the route from Castro Valley, CA
This is one driving day of about 402.1 miles and 7h 26m.
Your first comfortable stop window is around 88 miles from Castro Valley, CA.
This route can stay practical as a one-day drive if traffic stays reasonable.
Plan about 2 real breaks rather than only quick fuel stops.
The longest stretch is on Westside Freeway for about 224.4 miles.
Where to Stop
Rest stops, refuel points, and overnight suggestions along this route.
Place data sourced from public business listings. Hours and availability may vary.
Heads-up: tricky spots
5 of 20
5 decision points cluster between mile 0.3 and 398.8 — GPS handles the exact turns, but know they're coming. Your lane choice matters more than the turn itself.
7
0.3 mi into trip|~0m in|Strobridge Avenue
Turn left onto Strobridge Avenue
Lane positioning matters here
Use the straight lane.
6
11.9 mi into trip|~14m in|I 580 / Arthur H. Breed Junior Freeway
Keep slight right at fork onto I 580 / Arthur H. Breed Junior Freeway
Highway fork - watch signs carefully. Lane positioning matters here
Use the straight / slight right lanes.
7
331.5 mi into trip|~6h 3m in
Take the exit toward I 210 East: Pasadena
Exit ramp - move to the correct lane early. Lane positioning matters here
Use the slight right lane.
Exit 161A
Toward I 210 East: Pasadena
8
356.2 mi into trip|~6h 31m in|I 210 / Foothill Freeway
Keep slight right at fork onto I 210 / Foothill Freeway toward CA 134 West, I 210 East: San Bernardino, Ventura
Highway fork - watch signs carefully. Lane positioning matters here. Multiple destination signs - pick the right one
Use the slight right lane.
Toward CA 134 West, I 210 East: San Bernardino,...
7
398.8 mi into trip|~7h 20m in
Take the exit toward Sierra Avenue
Exit ramp - move to the correct lane early. Lane positioning matters here
Use the straight / slight right lanes.
Exit 67
Toward Sierra Avenue
Fuel & Cost
Regular Gas
$84.12 one way
$168.25 round trip
$5.31/gal25.4 MPG avg141 kg CO2
Fuel Type
$/gal
One Way
Round Trip
midgrade
$5.52
$87.37
$174.74
premium
$5.67
$89.68
$179.36
diesel
$4.80
$75.92
$151.85
No toll roads detected on this route.
Estimated Trip Cost (one way, 1 person)
Fuel
$84
Meals
$25–$50
Total
$109–$134
Rough estimate based on US averages. Hotel $80–$140/night, meals $25–$50/day.
Estimated CO2 emission: 140.7 kg one way.
Prices: EIA weekly data, 2026-07-13.
Driving Electric?
About $42 in charging
· 1 stop
· 67% less CO2
Vehicle Type
kWh
Stops
DC Fast
Home Charge
Average EV
120.6
1
$42.22
$19.30
Efficient EV
100.5
1
$35.18
$16.08
EV Truck/SUV
160.8
2
$56.29
$25.73
Gas CO2
141 kg
EV CO2
47 kg (67% less)
Plan for 1 charging stop. A 30-minute DC fast charge mid-route should be enough to complete the trip comfortably.
DC fast charging avg $0.35/kWh. Home charging avg $0.16/kWh. US grid CO2: 0.39 kg/kWh.
Travel Intel
Current conditions at both ends of the drive.
Forecast as of Jul 17, 2026
Origin
Castro Valley, CA
Late night
in Castro Valley on Sunday
Local time
1:15 AM
PDT
Current temp
56°F
Partly Cloudy
SW 6 to 9 mph2% chanceLive forecast
Heat Advisory
Heat Advisory issued July 16 at 12:00PM PDT until July 16 at 11:00PM PDT by NWS Hanford CA
Red Flag Warning
Red Flag Warning issued July 16 at 11:39AM PDT until July 17 at 8:00PM PDT by NWS Medford OR
Destination
Fontana, CA
Late night
in Fontana on Sunday
Local time
1:15 AM
PDT
Current temp
67°F
Mostly Clear
SW 0 to 10 mph3% chanceLive forecast
Heat Advisory
Heat Advisory issued July 16 at 12:00PM PDT until July 16 at 11:00PM PDT by NWS Hanford CA
Red Flag Warning
Red Flag Warning issued July 16 at 11:39AM PDT until July 17 at 8:00PM PDT by NWS Medford OR
Seasonal Notes
Summer travel usually means heavier construction, hotter rest stops, and busier weekend traffic around major cities.
Winter travel shortens daylight, so a route that looks manageable on paper can feel much longer after dark.
Holiday weekends tend to make both departure and arrival windows slower than the raw route time suggests.
Time zone
Same local time
Origin and destination are on the same clock, so arrival timing is easier to judge at a glance.
Temperature spread
11 degrees warmer at arrival
A meaningful temperature swing is a good cue to rethink layers, water, and how soon you want to arrive.
Road read
7h 26m on the road
Start early — leave by 6-7 AM to arrive at a reasonable hour.
Weather data from the National Weather Service. Conditions may change; check closer to your travel date.
National Parks Near This Route
Worth a detour if your schedule allows.
San Francisco Maritime National Historical Park
National Historical Park
Established in 1988, San Francisco Maritime National Historical Park celebrates America’s maritime heritage on the Pacific Coast. Our 50-acre park has grown around Aquatic Park Cove, a protected area...
Rosie the Riveter WWII Home Front National Historical Park
National Historical Park
Celebrate and honor the contributions and sacrifices of American civilians on the WWII home front. Discover how diverse communities lived, worked, and interacted. Many faces, many stories, many truths...
The Santa Monica Mountains offer easy access to surprisingly wild places. Experience the famous beaches of Malibu or explore more than 500 miles of trails. The park abounds with historical and cultura...
23 mi from route
~57 min detour
Free
near mile 332.8
On July 17, 1944, a massive explosion jolted the San Francisco East Bay area, shattering windows and lighting up the night sky. At Port Chicago Naval Magazine, 320 men were killed instantly when two s...
Yes, we can! Widely recognized as the most important Latino leader in the United States during the twentieth century, Cesar Chavez led farm workers and supporters in the establishment of the country's...
29 mi from route
~72 min detour
Free
near mile 263.4
Park data from the National Park Service API. Alerts update every 2 hours.
More Details
What kind of drive is this?
This trip is almost entirely on freeways, with a 99% highway share. You'll spend the bulk of your time on the Westside Freeway, which accounts for the longest continuous stretch at 224.4 miles. Expect frequent exits and on-ramps as you navigate through various urban and suburban corridors. The profile is mostly highway, so prepare for consistent speeds and the typical traffic patterns associated with major California interstates.
99% highway — fuel and pacing are the main things to plan.
23 navigation steps total — most of the decisions cluster near the start and finish.
Longest single stretch: 224.4 mi on Westside Freeway.
How Hard Is This Drive?
8/10
This is a straightforward highway drive that stays mostly on Westside Freeway and Foothill Freeway. This route has several spots where lane changes, forks, or exits need your full attention. The trickiest moment comes around 0.3 miles in near Strobridge Avenue.
Driving Effort8/10
Demanding - plan breaks and stay ahead of the key maneuvers
Balances navigation complexity with total wheel time.
This is a demanding drive. With 20 significant decision points across 402.1 miles, you will need to stay alert - especially through interchange areas and urban stretches. Consider splitting it into segments if you are not comfortable with fast highway navigation.
Where does it get tricky?
The main spots that need attention: at 0.3 miles (Strobridge Avenue): Lane positioning matters here; at 11.9 miles (I 580 / Arthur H. Breed Junior Freeway): Highway fork - watch signs carefully. Lane positioning matters here; at 331.5 miles: Exit ramp - move to the correct lane early. Lane positioning matters here.
Elevation Profile
High-altitude sections with notable climbs
3,851 ft154 ft
Total Climb
5,145 ft
Total Descent
4,072 ft
Highest Point
3,851 ft
~287.2 mi in
Elevation Range
3,697 ft
Notable High Points
3,851 ft at ~287.2 miles+2,614 ft prominence
Towns Mentioned on Route Signs
Based on OSRM destination-sign hints, not a full list of every settlement the road passes.
On the drive from Castro Valley, CA to Fontana, CA, road signs begin pointing toward Ventura along the way.
Castro Valley is an unincorporated town in the inner East Bay in the Bay Area of California. It has a population of about 60,000 and is located north of Hayward and east of San Leandro and south of the Oakland hills. Since it is unincorporated, Castro Valley is governed by the County of Alameda, which has its county seat in Oakland.
Doable as a same-day drive at 7h 26m. Total distance: 402.1 miles.
Family Friendly
Moderate complexity with 2 natural rest stops along the way.
Solo Traveler
7h 26m drive, plan rest stops for pacing.
Frequently Asked Questions
The longest stretch is about 224.4 miles on Westside Freeway. The full list of main roads is in the Roads section above.
Yes — we found about 34 rest areas or service plazas within a short detour of the route (from OpenStreetMap). See the Rest Stops tab under Nearby Places for locations and mile markers. Plan to stretch, use the bathroom, and top off fluids every 2–3 hours on longer drives.
It helps. This route has a higher-than-average number of complex decision points, which get harder in the dark. If the last hour of the trip is on surface roads or mountain grades, aim to arrive at Fontana, CA before sunset when you can. Check the Trip Plan for departure windows that land you in daylight.
Only with planning. This is a long drive for kids — consider splitting it into two days rather than pushing through. Plan at least 2 meaningful breaks. There are 34 rest areas along the route for bathroom stops.
The main spots that need attention: at 0.3 miles (Strobridge Avenue): Lane positioning matters here; at 11.9 miles (I 580 / Arthur H. Breed Junior Freeway): Highway fork - watch signs carefully. Lane positioning matters here; at 331.5 miles: Exit ramp - move to the correct lane early. Lane positioning matters here.
Yes — San Francisco Maritime National Historical Park, Rosie the Riveter WWII Home Front National Historical Park and Santa Monica Mountains National Recreation Area (5 total within detour distance). See the National Parks section for detour distances and tips on detours.
Not recommended in a single day. At 7.4 hours each way, a round trip means 14.9 hours of driving — that is an unsafe level of fatigue for most drivers. Plan at least one night at Fontana, CA before the return drive.
