Kozan-ji Buddha Hall: A Treasure of Kamakura Zen Architecture and Birthplace of the Restoration

Located in Chofu, Shimonoseki City, Yamaguchi Prefecture, Kozan-ji Buddha Hall is designated as a National Treasure as Japan's oldest Zen-style architecture with a confirmed date of construction in 1320 (Geno 2). This small Buddha hall not only perfectly embodies pure Zen architectural style but is also known as the historical stage where Takasugi Shinsaku launched the uprising that became the turning point for the Meiji Restoration. This temple, where architectural history and late Edo period history intersect, continues to convey Japanese spiritual culture across 700 years.

Architectural Style Expressing the Spiritual World of Zen

Kozan-ji Buddha Hall features a square floor plan of three bays by three bays with a single-story mokoshi (decorative pent roof), constructed in the irimoya-zukuri style with a cypress bark roof. Its greatest characteristic is its faithful embodiment of the Zen-style (Chinese-style) architectural standards that came from Song Dynasty China during the Kamakura period. The eaves feature densely arranged bracket complexes (tsumegumi), radiating fan rafters (ogi-daruki), and bell-shaped curved windows (katomado) - typical elements of Zen architecture visible throughout.

The interior raises the central bay to its highest point with a mirror ceiling, while the surrounding area exposes the structure as decorative roof framing. The outer mokoshi connects to the main structure through curved rainbow beams, becoming a lower decorative roof space, skillfully combining spaces of different heights using the unique framing methods characteristic of Zen architecture.

National Treasure Designation Proving Architectural Historical Value

Kozan-ji Buddha Hall received its National Treasure designation on November 14, 1953, due to its architectural historical importance. An ink inscription reading "This hall's pillars erected on the fifth day of the fourth month of Geno 2" remains on the upper part of the inner sanctuary's raigochu pillars, confirming the construction date and making it Japan's oldest Zen-style architecture with a definite date.

As a typical example of Zen-style Buddha halls, Kozan-ji Buddha Hall is mentioned alongside Engaku-ji's Shariden and holds extremely high value as an existing example showing the establishment period of architectural style that came from China with Zen Buddhism. During the dismantling and repair conducted in Taisho 7 (1918), the roof, which had been temporarily converted to tile, was restored to its original cypress bark covering, bringing it closer to its original appearance.

Highlights Condensing the Essence of Zen Architecture

The Buddha hall's highlights lie in the concentration of characteristic elements of Zen-style architecture. The flower-shaped windows (katomado) installed on both sides of the front create decorative window shapes with onion-shaped curves, producing the unique beauty of Zen style. The fan rafters under the eaves already radiate from slightly left and right of center in a characteristic arrangement, clearly distinguished from the corner fan rafters of the Great Buddha style.

The chimaki-bashira pillars that suddenly narrow and curve at the top and bottom, the base plates between pillars and foundation stones, the latticed Chinese doors across the front three bays - Zen aesthetic consciousness penetrates even the smallest details. The floor is not boarded but tiled earth, with tiles laid diagonally at 45-degree angles to the stone-paved edges in a quarter-tile pattern.

Journey to the Ancient Temple Blending into Chofu Castle Town

Kozan-ji Temple is located at 1-2-3 Kawabata, Chofu, Shimonoseki City, Yamaguchi Prefecture. From JR Shimonoseki Station, it's about 23 minutes by Sanden Kotsu bus to "Jokamachi Chofu" bus stop, then a 10-minute walk. Temple grounds viewing is free and open all day, while the study hall and garden admission is 300 yen for adults.

Nearby attractions include Chofu Mori Residence (10-minute walk), Chofu Garden (10-minute walk), and Shimonoseki City History Museum (across the street), scattered throughout the Chofu castle town tourist area. The autumn foliage season from late November to early December is known as one of Yamaguchi Prefecture's finest spots, with the contrast between the National Treasure Buddha Hall and bright red maple leaves creating a scenic autumn view.

The Turning Point to the Restoration Carved by Takasugi Shinsaku

Kozan-ji's historical value became decisive with Takasugi Shinsaku's uprising on December 15, 1864. After defeats at the Kinmon Incident and the bombardment of Shimonoseki by the Four-Nation Fleet, the Choshu Domain became an enemy of the Imperial Court with the conservative faction holding power. Against this, Takasugi Shinsaku decided to rise with just 80 men, carrying out the uprising in rare heavy snow for Shimonoseki.

Five nobles including Sanjo Sanetomi, who had been expelled from Kyoto, were staying at Kozan-ji. Takasugi declared "From now, I shall show you the skill of Choshu men" and received the ceremonial sake cup before departure. This uprising unified the Choshu Domain's policy toward overthrowing the shogunate, leading to the Satsuma-Choshu Alliance and victory in the Second Choshu Expedition, becoming the direct catalyst for the Meiji Restoration as the "Restoration's Revolutionary Banner Raising."