The Underground City is a novel with mystery and adventurous elements, set in a huge fantastic coal mine in Scotland.The story begins with James Starr, a mining engineer, receiving a letter from Mr. Ford, the retired overman of the now-depleted Aberfoyle mine.In the letter, Mr. Ford makes reference to new discoveries that have been made underground and invites Starr to visit.Starr receives a second letter at the same time asking him not to go.Unfazed, Starr joins Ford's son at the station, and both of them travel to the former mineshaft where Starr meets Mr. Ford, who actually resides in the mine in a cottage with his wife and kid, after cheerfully descending the 1,500-foot ladder.Now, the story is set in a coal mine that has been restored and is now prosperous.Later on, the story can amaze you with the pioneering of an underground city with electric lighting, a railway, and a central lake which is an interesting part to read How can people live and thrive 1500 feet below the surface of the earth?