Describe the Underground Railroad.

In 1831, a slave owner complained that his slave was aided in an escape by what he referred to as an "underground railroad." While this was the first known use of the term "underground railroad," this network of sympathizers, both African American and white, actually began their work in the late eighteenth century. George Washington, in 1786, attributed the escape of one of his slaves to Quakers. The goal of the Underground Railroad was to help slaves escape the South, with some traveling into free states in the North and some traveling as far north as Canada.
Terms used in railroading were also used for the Underground Railroad. For example, "conductors" were those that guided the slaves from one location to the next. Harriet Tubman was perhaps the most well-known conductor. "Stations" and "depots" were the homes or other locations where escaped slaves could find food and shelter. Those escaping slavery would typically travel at night and would be given information on how to locate the next safe place, or "station," along their route to the North.
https://www.history.com/topics/black-history/underground-railroad