Another word for underground railroad

PMF are spreading the word to the populace to hole up in the underground railroad.

She's not going to know about the underground railroad.

You're forgetting the underground railroad.

He started forward, anxious to see if the underground railroad survived the onslaught.

Special commissioners were to have concurrent jurisdiction with the U.S. circuit and district courts and the inferior courts of Territories in enforcing the law; fugitives could not testify in their own behalf; no trial by jury was provided; i The precise amount of organization in the Underground Railroad cannot be definitely ascertained because of the exaggerated use of the figure of railroading in the documents of the "presidents" of the road, Robert Purvis and Levi Coffin, and of its many "conductors," and their discussion of the "packages" and "freight" shipped by them.