Tahōtō
A tahōtō is a form of Japanese pagoda found primarily at Esoteric Shingon and Tendai school Buddhist temples. It is unique among pagodas because it has an even number of stories. Its name alludes to Tahō Nyorai, who appears seated in a many-jewelled pagoda in the eleventh chapter of the Lotus Sutra. With square lower and cylindrical upper parts, a mokoshi 'skirt roof', a pyramidal roof, and a finial, the tahōtō or the larger daitō was one of the seven halls of a Shingon temple. After the Heian period, the construction of pagodas in general declined, and new tahōtō became rare. Six examples, of which that at Ishiyama-dera is the earliest, have been designated National Treasures.
There are no examples in China, whether architectural or pictorial, of anything that resembles the tahōtō, although there is a Song dynasty textual reference to a tahōtō with an encircling chamber.
Hōtō
The hōtō or treasure pagoda is the ancestor of the tahōtō and dates to the introduction to Japan of Shingon and Tendai Buddhism in the ninth century. No wooden hōtō has survived, although modern copies do exist. They are usually made from stone, bronze, or iron, and specimens are always miniatures comprising a foundation stone, barrel-shaped body, pyramid roof, and a finial.Daitō
While the tahōtō is 3x3 ken, a larger 5x5 ken version exists, known as daitō or 'large pagoda'.This is the only type of tahōtō to retain the original structure with a row of pillars or a wall separating the corridor from the core of the structure, abolished in smaller pagodas. Daitō used to be common but, of all those ever built, only a few are still extant. One is at Wakayama prefecture's Negoro-ji, another at Kongōbu-ji, again in Wakayama, another at Kirihata-dera, Tokushima prefecture, another at Narita-san in Chiba. Kūkai himself, founder of the Shingon school, built the celebrated daitō for Kongōbu-ji on Kōyasan; almost fifty metres high, chronicles relate that 'the mightiness of its single storey outdoes that of multi-storeyed pagodas'. The specimen found at Negoro-ji is 30.85 meters tall and a National Treasure.