"Baron Trump's Marvellous Underground Journey" is a novel from a Baron Trump series written by Ingersoll Lockwood. In this book, Baron sets on an adventure in the land of Transparent Folk, the land of ant people, and the Happy Forgetters land. All these lands are placed deep below the dirt in Russia. They dread remembering anything and will, like history, forget Baron Trump soon after he goes above ground.

Ingersoll Lockwood (1841 - 1918) was an American lawyer and writer. As a writer, he is particularly known today for his Baron Trump children's novels. However, he wrote other children's novels, as well as the dystopian novel, 1900: or; The Last President, a play, and several non-fiction works. He wrote some of his non-fiction under the pseudonym Irwin Longman.