San Diego to Thermalito is 572.1 miles and takes about 10 hours 46 minutes via the Westside Freeway, San Diego Freeway, and Golden State Freeway, with a fuel budget near $125 and enough daylight to finish in a day if you start early. This is a long-haul drive that takes you across California, primarily on major freeways. Given the 10h 46m duration, most drivers will want to split this into two days. It's a practical route connecting two points in the Pacific Coast region, suitable for those needing to cover significant distance efficiently.
Trip Pace
Best split across 2 days
Treat the return leg as its own travel day rather than an afterthought.
Break Rhythm
3 planned breaks
Plan on a short reset every 3 to 4 hours to stay fresh behind the wheel.
Midpoint
286 miles from San Diego, CA
A natural place for your longest stop of the day
, about 5h 27m into the drive
.
Main Roads
Road
Distance
Duration
Westside Freeway
304.9 mi
5h 29m
San Diego Freeway
75.2 mi
1h 27m
Golden State Freeway
50 mi
57m
CA 70
47 mi
55m
I 5 Truck
45.3 mi
52m
Santa Ana Freeway
30.4 mi
35m
Golden State Highway
7.5 mi
8m
Bernie Richter Memorial Highway
5 mi
5m
Longest stretch:
Westside Freeway
— 304.9 mi, about 5h 29m
Traffic on I-5
Hour-of-day weekday pattern from 710 FHWA count stations on your route.
Peak
3 PM
~4,537 veh/hr typical
· worst 5,788
Quietest
2 AM
~597 veh/hr
Peak-to-quiet ratio
7.6×
busier at peak than in the quiet hours
12a6anoon6p11p
Averaged across 96 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 San Diego, CA and Thermalito, CA.
1
Start on Front Street
26 ft·6 sec·Front Street
2
Turn left onto West Broadway
290 ft·12 sec·West Broadway
3
Turn left onto 1st Avenue
0.6 mi·1 min·1st Avenue
Use the left lane.
4
Take the ramp
0.2 mi·24 sec
Toward I 5 North: Los AngelesUse the left / straight lanes.
5
Merge onto I 5
13 mi·15 min·San Diego Freeway
Use the straight / slight right lanes.
6
Keep slight left at fork onto I 5
36 mi·43 min·San Diego Freeway
Use the straight / slight right lanes.
7
Keep slight right at fork onto I 5
18 mi·20 min·San Diego Freeway
Use the straight / slight right lanes.
8
Keep slight left at fork onto I 5
7.4 mi·8 min·San Diego Freeway
Use the straight / slight right lanes.
9
Keep slight right at fork onto I 5 Truck
1.6 mi·1 min·I 5 Truck
Toward Bake ParkwayUse the straight / slight right lanes.
10
Keep slight right at fork onto I 5 Truck
6.0 mi·6 min·I 5 Truck
Use the slight right lane.
11
Take the exit
0.2 mi·16 sec
Exit 100Toward Jamboree RoadUse the slight right lane.
12
Continue on this road
527 ft·11 sec·this road
13
Turn right onto Jamboree Road
0.1 mi·18 sec·Jamboree Road
Use the left / right lanes.
14
Turn left onto El Camino Real
2.2 mi·4 min·El Camino Real
Use the left lane.
15
Turn left onto Newport Avenue
357 ft·13 sec·Newport Avenue
Use the left lane.
16
Take the ramp
0.2 mi·16 sec
Toward I 5 North: Los Angeles
17
Merge onto I 5
1.3 mi·1 min·Santa Ana Freeway
Use the straight / slight right lanes.
18
Keep slight right at fork onto I 5
1.7 mi·1 min·Santa Ana Freeway
19
Keep slight right at fork onto I 5
9.4 mi·10 min·Santa Ana Freeway
Use the slight right lane.
20
Keep slight right at fork onto I 5
18 mi·20 min·Santa Ana Freeway
Use the straight / slight right lanes.
21
Keep slight right at fork onto I 5
25 mi·29 min·Golden State Freeway
Use the straight / slight right lanes.
22
Keep slight left at fork onto I 5
2.2 mi·2 min·Golden State Freeway
Use the straight / slight right lanes.
23
Keep slight right at fork onto I 5 Truck
1.5 mi·1 min·I 5 Truck
Exit 161AToward I 5 Truck North, CA 14 TruckUse the straight / slight right lanes.
24
Keep slight left at fork onto I 5 Truck
36 mi·41 min·I 5 Truck
Use the straight / slight right lanes.
25
Keep slight left at fork onto I 5
22 mi·25 min·Golden State Freeway
Use the straight / slight right lanes.
26
Keep slight right at fork onto I 5
226 mi·4 hr 1 min·Westside Freeway
Toward I 5 NorthUse the straight / slight right lanes.
27
Keep slight right at fork onto I 5
26 mi·27 min·Westside Freeway
28
Keep left at fork onto I 5
54 mi·59 min·Westside Freeway
Use the straight / slight right lanes.
29
Keep slight right at fork onto CA 99
7.5 mi·8 min·Golden State Highway
Toward CA 99 North, CA 70: Yuba City, MarysvilleUse the straight / slight right lanes.
30
Continue on CA 99
5.0 mi·5 min·Bernie Richter Memorial Highway
31
Keep slight right at fork onto CA 70
22 mi·25 min·CA 70
Toward CA 70 North: Marysville, OrovilleUse the straight / slight right lanes.
32
Turn right onto 5th Street
0.2 mi·38 sec·5th Street
33
Turn left onto B Street
1.5 mi·3 min·B Street
Use the straight / right lanes.
34
Continue on CA 70
25 mi·29 min·CA 70
Use the left lane.
35
Take the exit
0.2 mi·20 sec
Toward Nelson Road
36
Turn left onto Grand Avenue
0.9 mi·2 min·Grand Avenue
37
Turn left onto 10th Street
0.2 mi·41 sec·10th Street
38
Arrive at destination
10th Street
Trip Plan
Given the 10 hour 46 minute estimated drive time, this trip is best split over two days. Aim to leave San Diego early in the morning to maximize your first day's driving. Plan for around 3 stops to break up the drive and refuel. The longest continuous stretch is over 300 miles, so make sure you're comfortable with extended periods behind the wheel or plan your overnight stop before reaching that point. Keep an eye on your fuel gauge, especially on the longer freeway segments, as services can be spaced out.
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.
This drive is better paced as a 2-day trip.
Plan roughly 3 meaningful breaks for fuel, food, and rest.
The halfway point lands around 286 miles from San Diego, CA, or about 5h 27m into the drive.
The longest continuous stretch on this route runs about 304.9 miles.
Consider an overnight stop or starting very early.
Departure
Before you leave
Start with fuel, water, and navigation already sorted so the first hour feels easy.
First stop
Around 126 miles or 2h 30m in
Use this first pause for coffee, a restroom break, and a quick traffic check ahead.
Halfway reset
Around 286 miles or 5h 27m in
This is the best place for your longest stop, a real meal, and a full fuel check.
Overnight split
Day 1 wrap after about 286 miles or 5h 27m
Stop before fatigue turns the last few hours into a grind. You want day two to start fresh, not just resumed.
Final approach
Final hour starts around 9h 32m
Traffic, exits, and arrival timing usually matter more near Thermalito, CA than in the middle of the route.
Before You Leave
+
Open the route before leaving San Diego, 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.
+
Treat this as a 2-day road trip and book the overnight stop before the busiest arrival window.
Day 1
Settle into the route from San Diego, CA
Aim for roughly 286 miles and 5.4 hours of wheel time on this day.
Day 2
Finish the approach into Thermalito, CA
Aim for roughly 286 miles and 5.4 hours of wheel time on this day.
Your first comfortable stop window is around 126 miles from San Diego, CA.
This route usually feels better as a 2-day drive than as one long push.
Plan about 3 real breaks rather than only quick fuel stops.
The longest stretch is on Westside Freeway for about 304.9 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 33
5 decision points cluster between mile 76.1 and 522 — GPS handles the exact turns, but know they're coming. Your lane choice matters more than the turn itself.
7
76.1 mi into trip|~1h 29m in|I 5 Truck
Keep slight right at fork onto I 5 Truck toward Bake Parkway
Highway fork - watch signs carefully. Lane positioning matters here
Use the straight / slight right lanes.
Toward Bake Parkway
7
83.7 mi into trip|~1h 38m in
Take the exit toward Jamboree Road
Exit ramp - move to the correct lane early. Lane positioning matters here
Use the slight right lane.
Exit 100
Toward Jamboree Road
9
144.7 mi into trip|~2h 52m in|I 5 Truck
Keep slight right at fork onto I 5 Truck toward I 5 Truck North, CA 14 Truck
Highway fork - watch signs carefully. Lane positioning matters here. Multiple destination signs - pick the right one
Use the straight / slight right lanes.
Exit 161A
Toward I 5 Truck North, CA 14 Truck
8
509.6 mi into trip|~9h 30m in|CA 99 / Golden State Highway
Keep slight right at fork onto CA 99 / Golden State Highway toward CA 99 North, CA 70: Yuba City, Marysville
Highway fork - watch signs carefully. Lane positioning matters here. Multiple destination signs - pick the right one
Use the straight / slight right lanes.
Toward CA 99 North, CA 70: Yuba City, Marysvill...
8
522 mi into trip|~9h 44m in|CA 70
Keep slight right at fork onto CA 70 toward CA 70 North: Marysville, Oroville
Highway fork - watch signs carefully. Lane positioning matters here. Multiple destination signs - pick the right one
Use the straight / slight right lanes.
Toward CA 70 North: Marysville, Oroville
Fuel & Cost
Regular Gas
$140.01 one way
$280.01 round trip
$6.22/gal25.4 MPG avg200 kg CO2
Fuel Type
$/gal
One Way
Round Trip
midgrade
$6.40
$144.17
$288.35
premium
$6.57
$147.89
$295.78
diesel
$6.18
$139.17
$278.35
No toll roads detected on this route.
Estimated Trip Cost (one way, 1 person)
Fuel
$140
Hotel (1n)
$80–$140
Meals
$50–$100
Total
$270–$380
Rough estimate based on US averages. Hotel $80–$140/night, meals $25–$50/day.
Estimated CO2 emission: 200.2 kg one way.
Prices: EIA weekly data, 2026-10-12.
Driving Electric?
About $60 in charging
· 2 stops
· 67% less CO2
Vehicle Type
kWh
Stops
DC Fast
Home Charge
Average EV
171.6
2
$60.07
$27.46
Efficient EV
143
1
$50.06
$22.88
EV Truck/SUV
228.8
2
$80.09
$36.61
Gas CO2
200 kg
EV CO2
67 kg (67% less)
Plan for 2 charging stops, roughly every 270 miles. Allow 25-40 minutes per stop at a DC fast charger.
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 Oct 18, 2026
Origin
San Diego, CA
Evening
in San Diego on Sunday
Local time
7:21 PM
PDT
Current temp
66°F
Mostly Clear
E 0 to 5 mph1% chanceLive forecast
Beach Hazards Statement
Beach Hazards Statement issued October 17 at 7:32PM PDT until October 20 at 9:00AM PDT by NWS Los Angeles/Oxnard CA
High Wind Warning
High Wind Warning issued October 17 at 11:53AM PDT until October 18 at 12:00AM PDT by NWS San Diego CA
Destination
Thermalito, CA
Evening
in Thermalito on Sunday
Local time
7:21 PM
PDT
Current temp
57°F
Clear
ENE 2 mph0% chanceLive forecast
Beach Hazards Statement
Beach Hazards Statement issued October 17 at 7:32PM PDT until October 20 at 9:00AM PDT by NWS Los Angeles/Oxnard CA
High Wind Warning
High Wind Warning issued October 17 at 11:53AM PDT until October 18 at 12:00AM PDT by NWS San Diego CA
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.
For long drives, weather on day two can matter just as much as conditions at departure, so check the whole travel window rather than only the first day.
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
9 degrees cooler at arrival
A meaningful temperature swing is a good cue to rethink layers, water, and how soon you want to arrive.
Road read
10h 46m on the road
This is long enough that the arrival forecast matters almost as much as departure conditions. Recheck both ends before you roll.
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.
Cabrillo National Monument
National Monument
In 1542, Juan Rodriguez Cabrillo climbed out of his boat and onto shore, becoming the first European to set foot on what is now the West Coast of the United States. Cabrillo National Monument not only...
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...
22 mi from route
~56 min detour
Free
near mile 138.1
Park data from the National Park Service API. Alerts update every 2 hours.
More Details
What kind of drive is this?
This route is predominantly highway, with 97% of the 572.1 miles on freeways like the Westside Freeway, San Diego Freeway, and Golden State Freeway. You'll experience a longest stretch of 304.9 miles on the Westside Freeway before encountering any significant surface roads. Expect consistent freeway cruising for most of the trip, with the potential for dense exit traffic as you move through populated areas.
97% highway — fuel and pacing are the main things to plan.
38 navigation steps total — most of the decisions cluster near the start and finish.
Longest single stretch: 304.9 mi on Westside Freeway.
How Hard Is This Drive?
8/10
This is a straightforward highway drive that stays mostly on Westside Freeway and San Diego Freeway. This route has several spots where lane changes, forks, or exits need your full attention. The trickiest moment comes around 76.1 miles in near I 5 Truck.
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 33 significant decision points across 572.1 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 76.1 miles (I 5 Truck): Highway fork - watch signs carefully. Lane positioning matters here; at 83.7 miles: Exit ramp - move to the correct lane early. Lane positioning matters here; at 144.7 miles (I 5 Truck): Highway fork - watch signs carefully. Lane positioning matters here. Multiple destination signs - pick the right one.
Elevation Profile
Gently rolling terrain
1,725 ft17 ft
Total Climb
2,152 ft
Total Descent
1,965 ft
Highest Point
1,725 ft
~163.5 mi in
Elevation Range
1,707 ft
Notable High Points
1,725 ft at ~163.5 miles+745 ft prominence
Towns Mentioned on Route Signs
Based on OSRM destination-sign hints, not a full list of every settlement the road passes.
Between San Diego, CA and Thermalito, CA, road signs point toward Marysville and Oroville.
From balmy beaches with a laid-back attitude to a gleaming modern image, San Diego offers much for the tourist to enjoy. Situated on the Southern California seacoast, San Diego is the second largest city in the state, with 1.4 million residents (2020), and has long attracted travelers for its ideal climate, miles of beaches, and location on the Mexican border right across from Tijuana.
But there's much more here than surfer culture and a quick hop across the border. A rich maritime and military heritage lives on in San Diego, which is home to the Pacific Fleet of the United States Navy. The city has also become known for its part in the wildlife conservation movement, owing to the presence of the world-renowned San Diego Zoo and Safari Park and the Scripps Institution of Oceanography. Natural scenery abounds from rocky tidepools and seaside cliffs to desert hills and canyons inland.
Top landmarks
•San Diego Zoo — zoo in Balboa Park, San Diego, California, United States
•Balboa Park — historic park in San Diego, California
The longest stretch is about 304.9 miles on Westside Freeway. The full list of main roads is in the Roads section above.
Yes — a 2-day pace is more comfortable than one long haul. A sensible stopping point is after roughly 286 miles on day one.
We did not find dedicated rest areas on this route. For a drive this long, plan bathroom and stretch breaks around gas stations, fast-food stops, or small-town downtowns — check the Nearby Places section for options.
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 Thermalito, 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 3 meaningful breaks. Dedicated rest areas are limited, so plan gas or food stops as your bathroom breaks.
The main spots that need attention: at 76.1 miles (I 5 Truck): Highway fork - watch signs carefully. Lane positioning matters here; at 83.7 miles: Exit ramp - move to the correct lane early. Lane positioning matters here; at 144.7 miles (I 5 Truck): Highway fork - watch signs carefully. Lane positioning matters here. Multiple destination signs - pick the right one.
Yes — Cabrillo National Monument and Santa Monica Mountains National Recreation Area. See the National Parks section for detour distances and tips on detours.
Not recommended in a single day. At 10.8 hours each way, a round trip means 21.5 hours of driving — that is an unsafe level of fatigue for most drivers. Plan at least one night at Thermalito, CA before the return drive.
