 Complete the following phrase:  Still worked with other Underground Railroad agents operating in the South, including in Virginia ports, nearby Delaware and Maryland, and in many counties in southern Pennsylvania. His network to freedom also included agents in New Jersey, New York, New England and Canada. Conductor Harriet Tubman traveled through his office with fellow passengers on several occasions during the 1850s. Still also forged a connection with the family of John Brown, and sheltered several of Browns associates fleeing the 1859 