Honkakuji Temple is a historic Buddhist temple in Shirahama, Wakayama Prefecture. Belonging to the Chinzei branch of the Jodo Buddhist tradition and affiliated with Chion-in Temple in Kyoto, it is affectionately known by local people as “Kai-dera,” meaning the “Shell Temple.”
What makes Honkakuji particularly unusual is its remarkable collection of seashells. The temple houses and displays more than 30,000 shells representing around 1,000 species, making it a fascinating destination for visitors interested in marine life, natural history, and the unique culture of this coastal town.
The temple is approximately 20 minutes by car from the Nanki-Shirahama Interchange on the Kisei Expressway. It is also conveniently located near popular Shirahama attractions such as Shirarahama Beach and Engetsu Island. The temple attracts not only tourists but also researchers and shell enthusiasts from Japan and beyond.
Honkakuji has maintained a close connection with the sea for centuries. Local fishermen are said to have donated unusual and beautiful shells they discovered while working at sea. Over generations, these donations gradually developed into a remarkable collection.
Today, the temple has more than 30,000 shells from approximately 1,000 species. The exhibition includes colorful shells, unusual shapes, and scientifically valuable specimens. The collection gives the exhibition room the atmosphere of a small natural history museum.
In 1929, a new species of shell discovered in Shirahama was named Honkakuji-higai, after the temple. This reflects the important role Honkakuji has played in the collection and study of shells.
The exact date of Honkakuji’s foundation is uncertain. According to the temple’s historical records, it is believed to have been established in 1633. Another tradition suggests that the temple may have been founded much earlier, during the Onin period from 1467 to 1469.
The temple was originally a Shingon Buddhist temple located in Okudera-dani, near Shirarahama Beach. During the Genroku period, it was moved to its present location and converted to Jodo Buddhism.
Honkakuji also has a particularly strong historical connection with the Kishu Domain, one of the most important feudal domains ruled by the Tokugawa family. Tokugawa Yorinobu, the founder of the Kishu branch of the Tokugawa family, as well as the second lord, Tokugawa Mitsusada, and Tokugawa Yoshimune, who later became the eighth shogun of Japan, are all said to have visited the temple on several occasions.
The temple was also known for presenting unusual shells to the domain lords. Memorial tablets dedicated to successive lords of the Kishu Domain remain enshrined at Honkakuji, while objects associated with the Tokugawa family can still be found on the temple grounds.
In 1781, with the support of the Kishu Domain, Honkakuji was elevated from a subordinate temple of Ryusenji Temple in Tanabe to a temple directly affiliated with Chion-in in Kyoto.
The Kishu Tokugawa family also donated ceremonial curtains bearing the Tokugawa hollyhock crest, lanterns, Buddhist ritual implements, and other items. Through these connections, Honkakuji developed into a temple of considerable prestige and importance.
The main attraction at Honkakuji is undoubtedly its Shell Exhibition Room. Shells from many different parts of the world are displayed here, offering visitors a fascinating look at the extraordinary variety of forms and colors found in nature.
Among the specimens are shells such as Miyakodorigai and Kawa-aigai, which are admired for their distinctive shapes and beautiful patterns. Together, the collection resembles a gallery of natural artwork.
You do not need to be an expert in marine biology to enjoy the exhibition. The diversity of the shells makes it an interesting experience for both adults and children, and it provides an opportunity to learn about the natural world in a relaxed setting.
Admission to the exhibition is based on a voluntary contribution. Visitors can take their time exploring the collection while enjoying the peaceful atmosphere of this historic temple.
Honkakuji is also associated with a romantic local legend known as the “Legend of Mashirara-hime.” The story adds a literary and mythical dimension to the temple’s connection with the sea and its shells.
According to the legend, a beautiful young woman named Mashirara-hime lived by the sea in Shirahama. One day, she met a young man who had traveled from the capital. The two fell in love, but the young man eventually had to return to the capital. Before parting, they exchanged a pair of shells as a promise that they would meet again.
However, the young man was actually Prince Arima, a historical figure remembered for his tragic fate. After returning to the capital, he lost his life. Mashirara-hime was unaware of what had happened and is said to have continued waiting for him by the sea.
Later, a beautiful pair of shells discovered along the coast came to be associated with Honkakuji-higai. They are displayed at Honkakuji as a symbol of the couple’s enduring love.
At Yuzaki Beach Square in Shirahama, visitors can also see a statue of Mashirara-hime holding the Honkakuji-higai shells. The site evokes the romantic atmosphere of Japan’s ancient Manyo-period literature and legends.
Honkakuji has attracted not only religious visitors and shell researchers but also writers and poets. One notable visitor was Matsuse Seisei, a haiku poet known as a leading disciple of Masaoka Shiki.
During his visit to Shirahama, Seisei stopped at Honkakuji and composed a haiku inspired by the temple’s shells and scenery:
“After looking at the shells, I gazed at the bellflowers.”
A monument commemorating the poem stands on the temple grounds, allowing visitors to experience a connection between the peaceful temple environment and Japanese literary culture.
The temple also preserves a monument bearing the sacred name of Tokuhon Shonin, a renowned Buddhist monk of the mid-Edo period. This monument provides another reminder of the long religious history associated with Honkakuji.
Honkakuji is conveniently located near several of Shirahama’s major tourist attractions, including Shirarahama Beach, Engetsu Island, and Shirahama Fisherman’s Wharf. At Fisherman’s Wharf, visitors can enjoy fresh seafood and browse for local souvenirs, making it an easy addition to a Shirahama sightseeing itinerary.
Honkakuji is much more than an ordinary Buddhist temple. Its extraordinary shell collection, connection with the Kishu Tokugawa family, local legends, literary associations, and long relationship with the sea make it a unique cultural attraction.
For international travelers, a visit to Honkakuji offers an opportunity to discover a less familiar side of Shirahama, where the ocean, natural history, Buddhist culture, local legends, and regional history come together.
If you are exploring Shirahama, consider stepping away from the better-known beaches and scenic viewpoints to visit this peaceful temple. The remarkable shell collection and stories preserved here provide a memorable glimpse into the natural and cultural heritage of this coastal community.