I could not just pick 3, so here are 4 photos from National Public Lands Day:
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It proves to be a hot day at the Castillo de San Marcos on National Public Lands Day.
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Families enjoy the large cannons atop the Castillo de San Marcos.
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Volunteers have the job of giving audiences a view into the past as they shoot off the cannons from the Castillo.
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Work is never boring for the volunteers on National Public Lands Day.
Finally, an "S" Curve at the Castillo: