The song is a ballad about Journey's city of origin, San Francisco, although it was actually written in and originally intended to be about Los Angeles. It was one of Steve Perry's first Journey songs, and was recorded soon after his joining the band. In an interview, Perry said, "I had the song written in Los Angeles almost completely except for the bridge and it was written about Los Angeles. It was 'when the lights go down in the city and the sun shines on LA.' I didn't like the way it sounded at the time. And so I just had it sitting back in the corner. Then life changed my plans once again, and I was now facing joining Journey. I love San Francisco, the bay, and the whole thing. 'The bay' fit so nice, 'When the lights go down in the city and the sun shines on the bay.' It was one of those early-morning-going-across-the-bridge things, when the sun was coming up and the lights were going down. It was perfect."

Released as a single in 1978, it was originally a minor hit, reaching number 68 on the Billboard Hot 100 at the time. It has, however, become more popular over the years and is now one of Journey's most popular and easily recognizable songs and is often played in Classic Hits/Oldies radio stations. It is frequently played at San Francisco Giants baseball games (including versions led by Perry himself at Game 2 of the 2010 World Series and Games 1 and 2 of the 2012 World Series) and the cross-bay Oakland Athletics after-game fireworks starts. The song is now usually played at Levi's Stadium when the NFL San Francisco 49ers win a home game. It is sometimes used in promos for the Golden State Warriors.

Journey released a live version of the song in 1993 for the Time³ box set.

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