Sasaya Pass, Mountain pass between Miyagi and Yamagata Prefectures, Japan

Sasaya Pass is a 906-metre mountain pass on the border of Miyagi and Yamagata Prefectures, crossed by National Route 286. The paved road narrows to a single lane with weight and length limits and closes in winter; the old route survives as walking trails, on the ridge one south on the Miyagi side and threading the current road on the Yamagata side.

Sasaya Pass is the oldest pass linking Miyagi and Yamagata. The Engishiki records a road from Tagajo to Akita Castle, with a Mogami post station on the Yamagata side, though its site is unconfirmed. In the Edo period the Sasaya Kaido was the main route between Sendai and Yamagata castles and was used for sankin kotai; a barrier stood at Sekizawa. The pass was improved for horse carts in 1893–1895 and is now followed by National Route 286.

The name is said to come from "sasayaki" (whispering), linked to the tragic-love legend of Princess Ako, though the tale is fiction and the many bamboo grasses (sasa) on the pass are the likelier origin. The Ako-no-Matsu pine and the Uyamauya barrier nearby appear in Heian-period poetry, and a stone monument at the pass bears a poem by Saito Mokichi.

The winding mountain roads require careful navigation, especially during winter when snow and ice affect driving conditions. Drivers should prepare for variable conditions and adjust their approach accordingly.

The old road survives beside the modern Route 286: on the Miyagi side it runs along the next ridge south, on the Yamagata side it weaves around the current road, and both sections are maintained as walking trails. Near the summit stands a stone monument inscribed with a poem by Saito Mokichi, who lived through the Meiji, Taisho and Showa eras.