Comments by "Sar Jim" (@sarjim4381) on "Coastal Defenses and The Endicott Era" video.

@andon_RT The fact the gun disappeared behind the parapet was not mostly for camouflage but ease loading, especially with muzzle loaders. Gunners could reload the guns without being exposed to direct fire, and parapets could be made higher to give better protection to the gun and crew. Once a gun fired, the enemy knew where it was located, so the disappearing advantage rapidly disappeared. The gun pits offered no protection from plunging fire and, later on, aircraft bombs. Most modern shore batteries had their breech loading guns in armored casemates or turrets to give better protection that just a parapet.
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The San Francisco harbor area has probably the most preserved forts and shore batteries, including a couple that were repurposed as Nike missile launch sites in the 50's. The are administered by the Golden Gate National Recreation Area (GGNRA). They provide a map of all the fortifications and short history of each. The last time I was there, about twenty sites still existed, the most of any area I know about. It will take you about two days to visit all of them, or a day to see the best preserved fortifications.
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