Raw from Ebay
David Hall: The San Francisco- Oakland Bay Bridge was opened to the public in November , 1936 and in the same month 100,055 Bay Bridge commemorative half dollars were struck at the San Francisco Mint. Interestingly, many were sold (at $1.50) in drive-up booths at the bridge itself. It was the first (and I think only) "drive-up" commemorative! In 1937, there were 28,631 Bay Bride half dollars melted as unsold making the distributed mintage a healthy 71,424 coins.
The healthy mintage has made the Bay Bridge one of the more readily available silver commemorative issues. It is also one of the only commemoratives of the 1930s that can be found somewhat easily in circulated condition. Nonetheless, most survivors grade MS63 to MS66. The typical Bay Bridge has nice frosty luster and eye appeal is usually quite good.