According to a Wikipedia entry, this bridge (known locally as “The Bay Bridge”) still has one of the longest spans in the world. Construction started in 1933, and the bridge was opened to traffic on November 12, 1936. Since this postcard states this was the longest bridge in the world, it brought up the question: What is the longest bridge in the world today? This depends on how you look at it. Do you count from beginning to end, or just the part over the water if water is involved? But just for contrast to the 8 1/2 miles listed for The Bay Bridge, the DanYang-Kunshan Grand Bridge in China, according to another Wikipedia entry, is 102.4 miles long, 5.6 miles of which is over open water.
Divided back, unused linen postcard. Circa 1936 – 1945. Publisher: Scenic View Card Co., 667 Mission St., San Francisco, California. “Nature Tone Views.” #43.