Geography
Matsushima Bay and the archipelago formed by the submersion of hills.
At the western edge of the Kitakami River, the Narese River in Higashi-Matsushima marks the westernmost point of the delta, beyond which lies the vast Matsushima Hills. Nanakita River and Shiogama lie to the south of this circular hill area, and Yoshida River to the north. Matsushima Bay was formed when the sea level rose after an ancient ice age and part of the hills submerged. The bay is shallow, with its depth ranging from approximately 1 to 4 meters, and it is an archipelago with around 260 islands.
The Sendai Plain born from the Ou Mountain Range.
The coast from Matsushima Hills to Soma, the endpoint (or starting point) of the trail, is predominantly flat. The Sendai Plain is adjacent to the Matsushima Hills to the south. Broadly speaking, the Sendai Plain is the largest plain in the Tohoku region, occupying most of Miyagi Prefecture, extending from Tome in the north to Watari in the south. Matsushima Hills divide it into the Senboku Plain to the north and the Sennan Plain to the south. The rivers that formed the Sendai Plain flow from the Ou Mountain Range, the backbone of Tohoku region, which extend from the Natsudomari Peninsula in Aomori to the Nasu Mountain Range. Rivers that flow from the mountain ranges to the east, such as the Hasama River, Eai River, Naruse River, Hirose River, Natori River, and Abukuma River, formed the plain.
Unlike the ancient hundreds of millions year old geological formations like the Kitakami Mountains, the Ou Mountain contains is high mountains formed by uplifts of the ocean floor and volcanic activity that occurred after the Japanese archipelago began to form around 15 million years ago. Acting as a barrier between the Pacific side of Miyagi and Iwate and the Japan Sea side of Yamagata and Akita, the Ou Mountains have also blessed the region with abundant rivers and hot springs.
The Sendai Plain, the plain that forms Sendai itself, is a river terrace carved by the Hirose River. The upper, middle, and lower town terraces have formed from north to south, with the Hirose River flowing even lower than the lowest lower town terrace. Sendai Castle is located on a plateau across the Hirose River from the plain.
The Abukuma River, which nurtured Fukushima.
Located at the southern end of the Sendai Plain, the Abukuma River is the second longest among the rivers in Tohoku. Similar to how the Kitakami River flows southward between the Ou Mountain Range and the Kitakami Mountains, traversing the major cities of Iwate Prefecture, the Abukuma River flows northward between the Ou Mountain Range and the Abukuma Highlands, passing through the major cities of Fukushima Prefecture. Its source is at the foot of the Nasu Mountain Range, and it flows through Shirakawa, Koriyama, Nihonmatsu, and Fukushima before reaching the Pacific Ocean at Arahama in Watari, after passing through Shiroishi and Iwanuma in Miyagi Prefecture.
Towns and Routes
Town at the Forefront of the Yamato Administration
In the Sendai Plain, towns that were historical political stages begin to emerge. This region has seen repeated conquests by the Yamato administration over the local clan known as Emishi since the Kofun period. In the 7th century, when the Ritsuryo administration system was established and centralized control by the Yamato government was strengthened, administrative centers were established in the northernmost Mutsu Province. In the area of Sendai, the Koriyama Kanga and in Osaki, the Myodate Kanga were set up. The town of Tagajo served as the provincial capital of Musashi Province in the 8th century, and it was from here that repeated campaigns against the Emishi were conducted. The scale of the government office here was more than half the size of the Heijo Palace, which was established around that time. In 802, Sakanoue no Tamuramaro, dispatched as the General of the Conquest of the Emishi by the Imperial Court, finally forced the Emishi chieftain, Aterui, to surrender, securing the control of Mutsu Province. Subsequently, the Isawa Castle Stockade was constructed in the northern part of present-day Oshu City, and it became the new frontline headquarters, advancing the central government’s expansion northward.
The main arteries connecting Fukushima, Miyagi, and Iwate
The primary terrestrial artery of this region was the Oshu Route, or Oshu Kaido. It passes through major towns such as Shirakawa, Koriyama, Nihonmatsu, Fukushima, Shiroishi, and Iwanuma, running parallel to the Abukuma River as the main transportation route by land and water. The current Route 4 corresponds to this road. Beyond Natori, continuing along the Hirose River leads to Sendai, then traverses the Sendai Plain northward toward Osaki. The Oshu Kaido extends farther north, running alongside the Kitakami River from the vicinity of Hiraizumi, passing through major cities in Iwate Prefecture within the Kitakami Basin. A coastal route from the Arakawa River in Kanto passed through Shimosa, Hitachi, Iwaki, and Soma to Iwanuma, known as the Rikuzen Hama Kaido, or Rikuzen Coastal Route. The current Route 6 roughly corresponds to this road. The Hama Kaido merged with the Oshu Kaido at Iwanuma.
Towns Established by Transferred Military Commanders
Since the pacification of the Emishi, local powerful clans gradually gained strength as they were appointed to bureaucratic positions while central government officials were dispatched. By the late Heian period, the Fujiwara clan, said to be descended from the powerful Abe clan, held real power, and their base of operations, Hiraizumi, prospered. Although Minamoto no Yoritomo eventually destroyed the Oshu Fujiwara clan, thereafter, with each change in military government, clans that contributed were granted territories, and their bases flourished as towns. During the Kamakura period, the retainers Kasai clan established themselves in Hiraizumi, the Soma clan from Shimosa in Kodaka and the Iwaki in Iwaki. In the Muromachi period, the Osaki clan settled in Myojo Castle in Osaki, and the Nambu clan, which later became the rulers of Nambu domain, moved to Nukanobu-gun with Kunohe and Ichinohe. Then, during the Sengoku period, military commanders, such as the Date clan, originally based in Okitama (Yonezawa), Fukushima, and Date, were transferred to the territories of the Kasai and Osaki clans under Toyotomi Hideyoshi’s orders. They established their headquarters at Iwadeyama in Osaki. Later, they rebuilt the Sendai Castle, formerly the residence of the Kokubun clan, and renamed it under a new Chinese character as Sendai Castle, marking the beginning of Sendai’s development under the Date administration.
Water transportation linking the Sendai Plain
The Edo period was an era of logistics. Inland towns without ports relied on rivers and canals as their main transportation routes, and improvements to these routes progressed during that period. Date Masamune began the construction of the Teizan Canal, which was completed during the Meiji period. It was a plan to connect the Abukuma River, which collected goods from the major cities in present-day Fukushima Prefecture, with the Sendai Castle via the Natori River, the Nanakita River, and Matsushima Bay, where the domain’s outer port, Shiogama, was located. The development was divided into three stages, with the first being the Kobikibori canal, which connected the warehouses at the mouth of the Abukuma River with the Yuriage at the mouth of the Natori River. It was completed around 1600 and transported rice collected from the Abukuma River basin to the castle town via the Natori River and the Hirose River. The next canal built was the Ofunairibori canal, which connected Shiogama and the Nanakita River (1673). This canal also transported rice to the castle town by going upstream Nanakita River.
In the Meiji era, the need arose for a modern port capable of accommodating large ships, leading to the development of the Nobiru Port as Japan’s first modern harbor construction project. Ishinomaki had shallow waters at the mouth of the Kitakami River, and the port of Shiogama had a narrow width. Therefore, Nobiru, which was protected by Miyato Island and had deep waters and proximity to Ishinomaki and Shiogama, was considered as a candidate site. However, in 1881, just three years after the inner harbor was completed, a typhoon caused the breakwater to collapse, leading to the port’s abandonment. In conjunction with the construction of Nobiru Port, the Shinbori canal, located in the middle of the Teizan Canal mentioned previously, was excavated in 1889. Similarly, in anticipation of the harbor construction, the Kitakami Canal linking the Kitakami River with Nobiru and the Tona Canal (1884) connecting Nobiru with Matsushima Bay were also created. With these developments, a long water transportation route linking the Kitakami River to the Abukuma River was completed.
The East Sea Route to Edo
The Abukuma River was the most important waterway for transportation, but there were narrow and swift sections north of Fukushima. In 1664, Edo merchant Watanabe Tomoi improved these conditions, allowing stable transportation of rice to Arahama Minato at the river mouth. From Arahama Port, the rice was transferred to cargo ships and transported to Edo via the Tone River route from Choshi. Later, in 1670, Kawamura Zuiken improved the Abukuma River and, in the following year, developed a route directly to Edo via the Boso Peninsula for cargo ships. Large cargo ships, including the largest at the time, the Sengoku Bune boat, began operating from Arahama Port to Edo, completing the East Sea Route. Large cargo ships from Sakata on the Sea of Japan crossed the Tsugaru Strait, passed through Sanriku via Ishinomaki, Arahama, Choshi, Shimoda, and finally reached Edo, marking the beginning of full-scale maritime transport. It is said that a large amount of rice collected from the Kitakami River and transported to Ishinomaki was sent to Edo, with about one-third of the rice entering Edo at that time coming from the Date domain.