Mount Ena, Mountain summit in Gifu Prefecture, Japan.

Mount Ena is a 2,191 m peak at the southern end of the Kiso Mountains (Central Alps), on the border of Nakatsugawa in Gifu and Achi in Nagano. Its upper slopes are covered in dark conifer forest of Veitch's fir, southern Japanese hemlock and Yezo spruce, with deep ravines cutting the face. The summit ridge is rounded; a wooden observation tower stands by the triangulation point, and the Ena Shrine inner sanctuary sits just southeast of the highest point.

The mountain's old name, Enayama, comes from the afterbirth (ena) of Amaterasu, who according to tradition was born in Mino after Izanagi and Izanami crossed Misaka Pass; the placenta was buried on the peak. In 1767 the ascetic Kakumei opened the mountain, and Edo-period logging stripped its western slopes of their cypress and fir forest.

The name Ena comes from ena, the placenta: legend holds that Amaterasu was born here and her afterbirth was buried in the mountain, which old texts call Enayama or Enoyama. Ena Shrine, dedicated to Izanagi and Izanami, has its main sanctuary at the foot in Kawakami, Nakatsugawa, and its inner sanctuary on the summit, where seven small shrines stand, among them Kazuraki, Fuji, Kumano, Shinmei, Tsurugi and Ichinomiya. From Meiji to Taisho, improved trails brought white-robed pilgrims of the Ena-kō confraternity.

Four main hiking routes reach the summit: Kuroisawa, Misaka Pass, Hirogawara, and Maemiya trails each suit different fitness levels. Choose your route based on your experience and how much time you want to spend on the mountain.

The old name Funafuseyama ("boat-capsized mountain") came from the profile seen from certain angles, not from the comb-like shape visible from the Nobi Plain. The summit's first recorded foreign climber was Walter Weston on 11 May 1893; a bronze bust of him stands in Ena-san Weston Park at the Maemiya trailhead, and a Weston festival is held each 11 May.