Planning for Bay Area Rapid Transit (BART) began in the 1950s after the Key System had been dismantled.
The first passenger embarked on Sept. 11, 1972 on the first BART line, which ran between MacArthur and Fremont.
BART says we can expect to hear more about the 40th anniversary year in coming weeks, including special promotions and events.
If you decide to use Flickr to share your antique BART photos, remember to use the Creative Commons license and tag photos with BART40th. Contributions and suggestions can also be emailed to email@example.com.
How long have you been riding BART? What do you remember about past decades? How has the service changed? Share your BART memories in the comments below. Have an old photo? Click "upload" to share it.