APR 16 1969, APR 26 1969, APR 30 1969; Drawing Is Of Harriet Tubman, Conductor On The Underground Railroad; Students are Stanley Crews, 3210 Kearney St., and Lisa Johnson, 3615 Locust St. Harriet Tubman conducted some 300 salves to freedom in the north in [Getty Images]

APR 16 1969, APR 26 1969, APR 30 1969; Drawing Is Of Harriet Tubman, Conductor On The Underground Railroad; Students are Stanley Crews, 3210 Kearney St., and Lisa Johnson, 3615 Locust St. Harriet Tubman conducted some 300 salves to freedom in the north in 1850s.; (Photo By Bill Peters/The Denver Post via Getty Images)