MARIN COUNTY (CBS 5) – They are reminders of a time when war raged on the other side of the Pacific and the United States needed to beef up its defenses. In this Good Question: What’s inside those big concrete coastal batteries that line the Marin Headlands?

ANSWER: According to John Martini with the National Park Service, the system of concrete coastal batteries contained hundreds of 16-inch caliber artillery rounds and a large gun that could hit targets more than 25 miles out to sea.

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