Take the Horyu-ji pagoda as the benchmark
A five-story pagoda is a tower built to enshrine relics of the Buddha. The pagoda at Horyu-ji dates from the Asuka period; it is the oldest of its type surviving in Japan and is counted among the oldest wooden towers in the world. It stands about 32.5 meters from its base.
On the four sides of the first story, scenes from the Buddha's life are depicted. The north side shows his passing into nirvana, with his disciples mourning around him. The relics are said to lie beneath the base.
The central pillar through the middle
A central pillar, the shinbashira, stands at the heart of the tower. At Horyu-ji it is cypress felled in 594, and it runs through all five stories. The tiers are built with flexibly joined timber that absorbs the energy of earthquakes, according to the Japan Tourism Agency's multilingual commentary.
In the Agency's database, the structure field of each of these pagodas reads three-bay five-story pagoda. Three bays is the number of column spans on each side, and five stories means five tiers of roof. Only Horyu-ji adds mokoshi on the first story, giving the bottom tier one extra skirt roof. Sickles are attached to the finial at the top, one of the Seven Mysteries of Horyu-ji, said to ward off lightning.
According to the Japanese commentary, the Horyu-ji pagoda was struck by lightning in the Kamakura period and caught fire, though the damage was not severe. Lightning talismans were hung on each tier, and today lightning rods protect it.
Five National Treasure pagodas side by side
Here is a comparison based on the Agency's database. Horyu-ji (Ikaruga, Nara) dates from the Asuka period and has honkawara tile. Muro-ji (Uda, Nara) is early Heian with cypress bark. Daigo-ji (Kyoto) is mid-Heian with honkawara tile. The Haguro-san Five-Story Pagoda (Tsuruoka, Yamagata) is early Muromachi with wooden shingles. Rurikoji (Yamaguchi) is mid-Muromachi with cypress bark. Other five-story pagodas, such as those at To-ji and Myoo-in, are also National Treasures; these five serve as examples here.
All five are National Treasures with the same three-bay five-story structure. The difference lies in the roof material: tile at Horyu-ji and Daigo-ji, cypress bark at Muro-ji and Rurikoji, wooden shingle at Haguro-san. Even in towers of the same type, the color and texture of the roof largely shape the overall impression.
The roof materials also tie in with the roofing article. Hiwada roofing uses cypress bark and kokera roofing uses wooden boards; both became Selected Conservation Techniques in 1976, and honkawara tiling was selected in 1994. Muro-ji and Rurikoji have the bark roof, Haguro-san the shingle roof, and Horyu-ji and Daigo-ji tile roofs.
Lined up, the five span from the Asuka period to the mid-Muromachi period (the Rurikoji pagoda dates from 1442), a stretch of more than 700 years. The Asuka period runs from 593 to 710. Even so the structure field reads the same three-bay five-story pagoda throughout, which shows how long the form was handed down.
Seeing the pagoda within its temple complex
A pagoda is not a stand-alone building but part of a temple's group of buildings. At Horyu-ji the Kondo and the five-story pagoda are both recorded as Asuka-period buildings, and 18 designations in all are National Treasures. At Muro-ji the pagoda and the Kondo are early Heian and the Hondo (Kanjo-do) is late Kamakura, three buildings in all being National Treasures. Under the name Daigo-ji four buildings are National Treasures, from the pagoda of 952 to the Seiryu-gu worship hall of 1434. At Haguro-san, a single pagoda alone is designated.
At Rurikoji too, the five-story pagoda is the only National Treasure building. At these two sites the pagoda is the only National Treasure building.
A viewing order, and avoiding mix-ups
It is easiest to go from bottom to top: the base and first story, the five stacked roofs, then the finial at the summit. On the roofs, look at the material and the size of each tier; at the finial, check for attachments as at Horyu-ji.
Some National Treasure towers are not five-story. The East Pagoda of Yakushi-ji is recorded as a three-bay, three-story pagoda with a mokoshi on every tier, so it shows six roofs. The Octagonal Three-Story Pagoda of Anraku-ji dates from the late Kamakura period, is octagonal in plan, has a mokoshi on the first story and is roofed in wooden shingle. Checking whether the structure field says five-story or three-story before counting roofs prevents mix-ups.
The designation dates of the five can also be compared. The pagodas of Horyu-ji, Muro-ji and Daigo-ji were all designated on 9 June 1951, Rurikoji on 22 November 1952 and Haguro-san on 11 June 1966.