Was there an actual railroad engine running underground as per novel by Colson Whitehead

Was there an actual railroad engine underground where? Since you mentioned the novel I'm going to guess that your question is asking if The National underground railroad used to escape slavery in North America, was a literal locamotive with a engine. If that's so then no it was a series of trails, houses and other locations that led to an assumed place of freedom for those that were enslaved to advance the economy. As mentioned by Colson Whitehead, he imagined it as a literal train as a child and wrote the novel from that. If not asking about the underground railroad for slaves to escape slavery. Then yes some rails do run underground with an engine running.

No