Originally a grand entrance to the city of Seoul, today traffic flows around instead of through Sungnyemun Gate. It has been preserved through the centuries as the city grew up around it and expanded. Today the gate is the oldest wooden structure in Seoul and is considered a national treasure. It used to be that all visiting dignitaries were required to pass through this gate to enter the city. The gate, itself, is made of granite blocks forming a huge granite block with an arched passage through the middle. Resting on top of this structure is a traditional two-story pavilion. The gate was formerly flanked by walls protecting the city, but these were razed by the Japanese.