Kamakura's Seven Entrances

The city of Kamakura, Kanagawa in Japan, is closed off on three sides by very steep hills and on the fourth by the sea: before the construction of several modern tunnels and roads, the so-called Seven Entrances (Nana-guchi), or Seven Passes (Nana-kiridoshi 七切り通し) (all artificial) were its main links to the rest of the world. The city was therefore a natural fortress and, according to the Azuma Kagami, it was chosen by Minamoto no Yoritomo as his base specifically for this reason. The name itself seems to have been modeled on that of Kyoto's Seven Entrances (京都七口)—sometimes translated as the seven "mouths"—which first appears in the literature of the intermediate Muromachi period (around the year 1450). Together with the other "numbered" names like "Kamakura's Ten Wells" and "Kamakura's Ten Bridges", the modern "Seven Entrances" is an Edo period invention probably concocted to stimulate tourism. The Azuma Kagami calls them simply -zaka: Kobukurozaka, Daibutsuzaka, Gokurakuzaka, etc. It must also be noted that, besides these seven, there were always other mountain roads that connected Kamakura with, for example, Kotsubo and Shichirigahama. There is one, for example, that connects Kaizō-ji in Ōgigayatsu with Kita-Kamakura Station. The Seven Entrances were simply the most convenient and important.

While economically vital because they allowed traffic to and from the outside world, the Seven Passes had also great military value, and as such they were fortified in various ways, for example narrowing them further until a horse could barely pass through, and obstructing the view of incomers. The roads were also modified adding artificial cliffs and forts from which archers could hit enemies below.

Also known as Mutsuurakuchi (六浦口) and commonly called Asahina Pass (朝比奈切通), the Asaina Pass (朝夷奈切通) connected Kanazawa (today part of the city of Yokohama) to Kamakura, while at the same time protecting its eastern flank. The Azuma Kagami reports that the decision to link the city to Kanazawa was taken in 1240 by Shikken Hōjō Yasutoki. Its name seems to stem from the legend that superhuman hero Asahina (or Asaina) Saburō Yoshihide (a historical figure and Wada Yoshimori's third son) built it by himself in one night. The falls near the Kamakura entrance to the pass, the Saburō Falls (三郎滝), are also named after him. The whole pass has been declared a historical landmark.

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Wikipedia