Underground Railroad, in theUnited States, a system existing in the Northern states before the Civil War by which escaped slaves from the South were secretly helped bysympathetic Northerners, in defiance of theFugitive Slave Acts, to reach places of safety in the North or inCanada. Though neither underground nor a railroad, it was thus named because its activities had to be carried out in secret, using darkness or disguise, and because railway terms were used in reference to the conduct of the system. Various routes were lines, stopping places were called stations, those who aided along the way were conductors, and their charges were known as packages or freight. The network of routes extended in all directions throughout 14 Northern states and “the promised land” of Canada, which was beyond the reach of fugitive-slave hunters. Those who most actively assisted slaves to escape by way of the “railroad” were members of the free blackcommunity (including such former slaves asHarriet Tubman), Northern abolitionists, philanthropists, and such church leaders as Quaker Thomas Garrett.Harriet Beecher Stowe, famous for her novelUncle Tom’s Cabin, gained firsthand knowledge of fugitive slaves through her contact with the Underground Railroad in Cincinnati, Ohio.

Estimates of the number of black people who reached freedom vary greatly, from 40,000 to 100,000. Although only a small minority of Northerners participated in the Underground Railroad, its existence did much to arouse Northern sympathy for the lot of the slave in theantebellum period, at the same time convincing many Southerners that the North as a whole would never peaceably allow the institution ofslavery to remain unchallenged.