FREDERICK, Md. (AP) — The National Park Service is holding events at two Civil War battlefields to mark the 150th anniversary of the end of slavery in Maryland.

Saturday’s events include two lectures and a special exhibit at the Monocacy (mah-NAH’-kah-see) National Battlefield near Frederick. The artifacts include chains purportedly worn by Maria Toogood, an Anne Arundel County woman who has been called the last slave in Maryland.

The Antietam National Battlefield near Sharpsburg is co-hosting a series of lectures with the Friends of Tolson Chapel. The nearby chapel housed a school for freed slaves.

President Abraham Lincoln signed the Emancipation Proclamation in 1863, but slavery remained in place in Maryland until Nov. 1, 1864. That’s when Maryland amended its constitution, more than a year before the 13th Amendment abolished slavery nationwide.

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