What is the Pennsylvania anti slavery secret mission?

The Pennsylvania Anti-Slavery Secret Mission was a network of safe houses and routes used to transport enslaved people to freedom in Pennsylvania prior to the end of the American Civil War. The mission was organized and led by Quaker abolitionists and was part of a larger network of safe houses and routes known as the Underground Railroad. The mission was headquartered in Philadelphia, Pennsylvania, and operated from the 1820s to the early 1860s.