In the municipality, the history of the Arai Barrier, seasonal festivals and experiences at the meeting point of Lake Hamana and the Pacific Ocean each offer a different focus. If you choose Kosai as your overnight destination, you can plan your stay around culture, scenery or special event days.
History of the Arai Barrier
In the municipality, the Arai Barrier, also known as the Imagiri Barrier, was established in 1600 next to the Imagiri ferry landing. After being moved following a storm in 1699, it was relocated to its present site the year after the 1707 earthquake and tsunami. The surviving structure is the only barrier building in Japan preserved unchanged. It was designated a Historic Site in 1921 and a Special Historic Site in 1955.
In the municipality, the Sekisho Museum associated with the barrier permanently displays materials about the barrier and the history of roads and transportation. Six to seven special exhibitions are held there each year. This connects the history of the building with a broader view of former transportation routes. The Toyota Sakichi Memorial Museum in the municipality displays many of the looms invented by Sakichi Toyota, along with mementos from his life. The exhibits are arranged around Sakichi Toyota’s birthplace.
Seasonal dates and experiences
If you are planning your trip around a festival, you can use these recurring dates as a guide. In the municipality, the plant market at Tōunji is held every year on the fourth Sunday in February. Hanamatsuri, which commemorates Buddha’s birthday, is usually celebrated in early April in the park by Honkoji; the date may vary. If you plan to attend either festival, check the date for your travel year in advance.
In the municipality, Imagiriguchi Taiken no Sato Kaikokan at Imagiriguchi, the passage between Lake Hamana and the Pacific Ocean, offers water-related educational activities, barbecue facilities and bicycle rentals. The adjoining Kirakuichi Shokudo also offers seasonal experiences: in summer, these include catching eels and then grilling them, fishing, and an activity involving Kamataki-Shirasu. The oyster hut opens in winter. The restaurant is open on event days; check which days are scheduled before visiting.
Scenery on Lake Hamana
In the municipality, a 51-meter-high ridge extends into Lake Hamana; the ruins of Utsuyama Castle are located on it. Today, the castle ruins serve as a viewpoint over Lake Hamana, linking the scenery with a historic site. The Kosai Mountains run along the western side of Kosai Municipality, following the border between Aichi and Shizuoka prefectures. There are numerous routes there for trekking and trail running.
In the municipality, you can buy seafood caught off Washizu and Irideshi at Washizu Fishing Port; you can also watch an auction there. Information about its operations was last updated in 2019; check current options before visiting.
The cultural sites, seasonal events and scenic spots each offer a different focus. When planning, consider which ones matter to you, and take the relevant dates into account for festivals and event activities.
Discover more destinations: Fujinomiya, Inatori Higashiizu, Kawazu, Gotemba, Shimoda, Atami, Fuji, Iwata
See the main travel overview: Shizuoka Prefecture.
