Two years ago, a big steel and concrete median barrier went in on the Golden Gate Bridge, and two yellow machines appeared that move it several times a day. Bridge commuters have some questions.

Reported by Kelly O'Mara. Bay Curious is Olivia Allen-Price, Vinnee Tong, Paul Lancour, Julia McEvoy, Penny Nelson and Suzie Racho. Theme music by Pat Mesiti-Miller.

Ask us a question at BayCurious.org.

Follow Olivia Allen-Price on Twitter @oallenprice.

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