DORCHESTER COUNTY, MD -- Weather played a significant role in the success of Harriet Tubman's missions to free enslaved people via the Underground Railroad.
The Harriet Tubman Underground Railroad National Historical Park is located in Dorchester County, Maryland, where Tubman was born. The museum shows visitors how Tubman used the weather and environment to her advantage.
According to her biography, she made 19 trips back to the South to guide groups of enslaved people to freedom.
Those trips were taken in the late fall or early winter. That helped avoid temperature extremes, but more importantly, it gave the escapees more night time to escape. The sun would be setting around 5 p.m. and would not rise until nearly 7 a.m.
"You have much longer to travel. During the day when the sun is out, it's much easier to see somebody in the woods -- to chase somebody and follow someone," park manager Angela Crenshaw said during an interview with AccuWeather.
The terrain that the escaping people had to travel over was also easier to navigate in the fall and early winter.
"The landscape here in Dorchester County is very tidal and very marshy so in the summer would've been squishy and wet," Crenshaw said. "In the summer, there are a lot of biting flies and mosquitoes and chiggers and things that are definitely a hindrance."
But if they waited too late and the cold of winter had set in, the ground could be frozen. That might have allowed the travelers to get off course, stepping on a place that appeared solid, but that actually gave way when you put your full weight on it.
In addition to the temperatures and length of night, finding a clear sky would be very helpful in making the trip.
Maps were not readily available, so the escaping group turned their eyes to the sky to navigate. The North Star was the most accurate navigational beacon available.
"God's time is always near. He set the North Star in the heavens. He gave me the strength in my limbs. He meant I should be free," Tubman has been quoted as saying.
Because the seasons played such an important role in Tubman's freedom journeys, the park installed stained-glass windows depicting the seasons.
For more information on the Harriet Tubman Underground Railroad National Historical Park, click here.