Rōmon is a traditional two-storied gate found in a place of worship in Japan. "Rō"means "multi-storied", and "mon" means "gate" in Japanese. A typical rōmon in Japan is constructed with wood; massive and decorative; and has a large hip-and-gable roof and a wraparound small balcony with railings. Rōmons that are noted for their artistic beauty and historical significance tend to belong to Shinto shrines. Yet no one can answer such simple question as how many rōmons exist in Shinto shrines in Japan. This very first book about Shinto rōmons has two parts. Part 1 is about reporting results of my search for existing Shinto rōmons across Japan. First, I explain the unique and systematic techniques I used to search for existing rōmons. Then I report findings from my search. Results are organized by various topics, such as time of construction, geographic location, relative spatial position, notable exterior characteristics, zuijin statues, and preservation of rōmons. Findings are primarily aggregated at the group level, but notable examples of individual cases (specific rōmons) are also provided. In short, Part 1 is designed to answer such basic questions as "What is rōmon?" "What do they look like?" and "Where are they located?" Part 2 is about lost Shinto rōmons. The existing rōmons are only a small part of the rōmons that have ever been built, and on average in every several years a rōmon is lost due to fire, earthquake, old age, among other reasons. Part 2 consists of a collection of fascinating stories and trivia of lost Shinto rōmons. These stories and trivia relate to specific shrines, famous persons, or historic events, and are organized chronologically. Examples of topics include "Iwashimizu Hachimangū - Eight Generations of Rōmons", "Kashiwahgi Jinja - Musical Chairs of Rōmons", "The Toyotomi Clan vs. the Tokugawa Clan - Who is the Rōmon Shogun?", "End of the Syncretism - Did Shinto Shrines Lose Rōmons?" and "A Forgotten Lost Shinto Rōmon Overseas." This book also contains 12 tables, 8 figures, a glossary of Shinto gates, and bibliography. Finally, the appendix lists all 225 existing rōmons, their locations, structural designs, and historic preservation designations.