Columbia subject headings:
Fugitive slaves--United States--History.
Historic sites--United States.
Slavery--United States--History.
Underground Railroad--History.
Harvard subject headings:
Fugitive slaves--United States--History.
Historic sites--United States
Slavery--United States--History
Underground Railroad
Princeton subject headings:
Fugitive slaves--United States--History.
Historic sites--United States.
Slavery--United States--History.
Underground Railroad--United States--History.