Is there a train between Union City and Castro Valley?

No, there is no direct rail connection; you would need to use AC Transit buses.

How long is the drive?

It typically takes 25 minutes under normal traffic conditions.

What is the best highway to take?

I-880 North to I-238 East is the most efficient route.

Are there tolls on this route?

No, there are no bridge or road tolls on this specific path.

Is public transit viable?

Public transit is available via AC Transit but takes significantly longer than driving.

Union City

Castro Valley

Driving

Union City to Castro Valley

Updated: 31 May 2026

The journey from Union City to Castro Valley covers approximately 15 miles through the heart of Alameda County. You will primarily utilize I-880 North before transitioning to I-580 East. Travel time typically ranges from 25 to 40 minutes depending on peak hour congestion. This route is a standard suburban commute for many East Bay residents. You will pass through Hayward, which serves as a major transit hub between these two locations.

Total Distance: 24 km driving distance; 18 km straight-line air distance.

Fastest Way

Driving via I-880 and I-238 is the fastest route, usually taking 25 minutes without traffic.

Cheapest Way

Driving your own vehicle is the most cost-effective method for this short distance.

Compare Union City to Castro Valley Routes

Driving

Direct

Duration

25 mins

Avg Price

5-8 dollars

Operator

Personal Vehicle

Route

I-880 North to I-580 East via the I-238 connector.

Use the I-238 connector to avoid local Hayward surface street traffic.

Travel Tips

Avoid Peak Hours
Traffic on I-580 East becomes extremely heavy between 4 PM and 6 PM.
Use Navigation Apps
Real-time traffic apps are essential for identifying accidents on the I-238 interchange.
Carpooling
Consider carpooling to utilize HOV lanes if you are traveling with another person.
Fuel Up Early
Gas prices in Castro Valley can be higher than in Union City; fill up before leaving.
Parking
Most regional parks in Castro Valley charge a small daily parking fee.

Safety Tips

Merge Carefully
The I-238 to I-580 merge is notoriously tight; maintain a safe following distance.
Road Conditions
Be cautious of slick roads during the winter rainy season.
Vehicle Maintenance
Ensure your tires are properly inflated for highway speeds.
Emergency Kit
Keep a basic emergency kit in your trunk even for short local trips.