Shanmen refers to the entrance gate of a Buddhist temple. In ancient times, nearly all Buddhist temples featured a single Shanmen gate that led into a large hall.
In contemporary Chinese architecture, most surviving Buddhist temples follow a hall style incorporating three main gates into their construction. Following periods of war and cultural discontinuity, many Chan Buddhist temples modified the middle gate into an entrance known as the "Hall of Shanmen." The Shanmen remains the most important gate within a Chan Buddhist temple.