Detailing the most reliable system in the US!
Discover the Bay Area Rapid Transit system—one of the world's most extensive and reliable public transportation networks connecting millions of passengers across California's Bay Area.
We’ll now shift our focus to the ground and explore the background of one of the best public transit systems in the world.
You might be thinking, “Brooke, this has nothing to do with travel—it’s just a bus line.” To that, I say—respectfully—you’re wrong on both counts. It’s actually a train system, and it serves millions of passengers each week.
Yes, some riders use it for daily commutes to work or school. But many others rely on it to travel to and from the three major airports in the Bay Area.
I am, of course, referring to the Bay Area Rapid Transit system (BART)—or, as locals call it, BART.
Running from the South Bay to San Francisco (with a key integrated stop at San Francisco International Airport, or SFO), across to the East Bay and Oakland, north to the University of California, Berkeley, and out to the valley—including Antioch, the terminus of the Yellow Line—BART offers extensive regional coverage. It also extends west to West Dublin in the Pleasanton area.
BART is nearly unparalleled in its ability to connect much of the Bay Area.
Future expansion plans include extending service south to Santa Clara and central San José, with key stops planned at San José Mineta International Airport (SJC) and Levi’s Stadium, home of the San Francisco 49ers. Currently, however, BART service does not extend beyond Milpitas into Silicon Valley.
Officially, BART serves large portions of three core counties—San Francisco, Alameda, and Contra Costa—as well as smaller areas of San Mateo and Santa Clara counties.
The system includes 50 stations across six color-coded lines and spans 131 miles of track. This includes:
- eBART, a 9-mile diesel-powered extension to Antioch
- The Oakland Airport Connector (OAC), a 3-mile automated guideway linking BART to Oakland International Airport (OAK)
The OAC requires a separate fare from the standard BART system.
As of the fourth quarter of 2025, BART averages approximately 186,000 weekday passenger trips and recorded over 55 million annual riders in 2025. This makes it the seventh-busiest rapid transit system in the United States—and one of the most reliable.
A Brief History
BART is operated by the San Francisco Bay Area Rapid Transit District, established in 1957.
Construction began in 1964, and passenger service launched on September 11, 1972, initially running between MacArthur and Fremont. The full system opened in 1974 with the completion of transbay service through the Transbay Tube.
Since then, the system has undergone several expansions, most recently in 2020 with the opening of Milpitas and Berryessa/North San José stations as part of the Silicon Valley extension in partnership with the Santa Clara Valley Transportation Authority (VTA).
Future phases aim to complete the extension deeper into Silicon Valley.
The Transbay Tube: An Engineering Marvel
The Transbay Tube is one of BART’s most remarkable features.
This underwater rail tunnel runs beneath San Francisco Bay, connecting Oakland and San Francisco. The tube itself is 3.6 miles (5.8 km) long, with the full rail segment between adjacent stations stretching approximately six miles.
At its deepest point, it reaches 135 feet below sea level.
Constructed using the immersed tube method, the structure was built in 57 sections on land, transported to the bay, submerged, and secured to the seabed using sand and gravel.
Opened in 1974, the Transbay Tube carries four of BART’s five main lines (Red, Blue, Yellow, and Green). During peak hours, it handles over 28,000 passengers per hour, making it one of the busiest segments of the system.
The Orange Line operates entirely within the East Bay and does not cross into San Francisco.
Service and Operations
All BART lines converge through Oakland, and most cross the bay into San Francisco via the Transbay Tube. Trains operate daily until 9 p.m., with reduced service afterward.
A unique operational feature exists on the eastern segment of the Yellow Line (between Antioch and Pittsburg/Bay Point), where passengers must transfer due to different rolling stock.
Late-Night and Early-Morning Service
When trains are not running, BART offers alternative bus services:
All Nighter Network (since 2006):
Provides overnight service across San Francisco, the East Bay, and parts of the Peninsula. These routes mirror BART lines but with shorter coverage.
Early Bird Express:
Operates between approximately 3:50 a.m. and 5:30 a.m., connecting major stations before train service begins. These routes are run by agencies such as AC Transit, Golden Gate Transit, Muni, and SamTrans.
Originally launched with 15 routes, the system was reduced to six in 2024 due to lower ridership.
Accessibility
BART partners with AC Transit to provide East Bay Paratransit, offering accessible transportation for passengers with disabilities who cannot use standard rail services.
Connectivity
BART is one of the most interconnected transit systems in the world.
It links with:
- Amtrak (California Zephyr, Capitol Corridor, San Joaquins) at Richmond and Oakland Coliseum
- Caltrain at Millbrae
- Muni Metro throughout San Francisco
- VTA Light Rail at Milpitas
Additional connections include regional bus systems such as VINE (Napa), Solano Express, and services from Stockton and Stanislaus County.
Many stations also serve private shuttles, hospital transit, and intercity buses.
Airport Access
BART directly serves:
- San Francisco International Airport (SFO)
- Oakland International Airport (OAK) via the Oakland Airport Connector
San José Mineta International Airport (SJC) is currently accessible via VTA bus connections from Milpitas, with future direct BART service planned.
Final Thoughts
BART is more than just a transit system—it is a critical backbone of mobility across the Bay Area. Its reach, connectivity, and ongoing expansion make it one of the most important transportation networks in the United States.
Thank you for reading. We hope you’ll consider visiting San Francisco or the greater Bay Area soon—and when you do, plan your trip through Brooke In The Air Travel at brookeintheairtravel.net.
