In the years preceding the American Civil War, many slaves used the Underground Railroad to escape to the north. Of those, a few returned to assist running that network of spies and contacts, to help others escape. The most famous of these freedom fighters was Harriet Tubman, a woman afflicted with seizures and “visions” due to head trauma meted out by an abusive master when Harriet was just 12 years old. Though she dreamed of freedom all her life, Harriet was 30 before the anti-slavery movement was able to help her get beyond the reach of slavery laws. She swept floors as a pretend maid and rode alone at night with nothing but the North Star as a guide, but after several months of travel and with the help of dozens of collaborators along the way, she reached the Canadian border.

Despite having just escaped three decades of indentured servitude, it was only a year before she was back to help others in find their freedom as well. In all, she is credited with getting more than 70 slaves to freedom in her time as a “conductor” of the Underground Railroad, and through her story with inspiring millions more.

Perhaps the best way to appreciate the road travelled by Tubman and the thousands of other slaves who fled the brutality of slavery is to travel it yourself. Purists will want to use carts and horses lit through the night with oil lamps, try to replicate the plight of these weary travellers, but most will opt for the modern approach; bicycle and driving tours exist for many routes through the former Underground Railroad, with stops at various preserved locations.

One of the most important localities in the Underground Railroad is Buffalo. As one of the northern-most cities in the United States, and one of the closest cities to the Canadian border, it served as the final stop for many escaping slaves. Walk through the Michigan Street Baptist Church in Buffalo, which housed untold numbers of slaves either disguised or hidden in compartments below the floorboards. The clout of the Church offered some amount of protection from inspectors, and to this day the Michigan Street Church is considered a landmark in the history of slave migration. Harriet Tubman used the Michigan Street parish multiple times, as it was both loyal and close to the Canadian border.

This crossing was mostly accomplished at the nearby Broderick Park, which now features a bridge but which required 19th-century slaves to swim. With the passing of the Fugitive Slave Law, even the northern states were unsafe for slaves on the run; a swim to the Canadian side of the Niagara River became a staple of the African American flight for freedom.

You needn’t make the pilgrimage to Buffalo just to appreciate the history of the Underground Railroad, however; the exodus of slaves spanned the whole of the country, and virtually every state in the country has some number of heritage sites preserved for just that purpose. From safe-houses in formerly radical pro-slavery states to militantly anti-Slavery hostels that openly courted fleeing slaves, there were plenty of candidates.

Not all of them were used by Harriet Tubman herself, of course, but they all embody the same spirit of courage and of defiance in the face of violent oppression.