The geology of the Kanehana slide areas consists primarily of the Cretaceous-Paleocene Yubetsu Group, Upper Miocene Ikutahara and Yahagi Formations, Late Miocene andesite and rhyolite dikes, Lower Pliocene Hakugindai Lava, and Quaternary System. The Ikutahara Formation is distributed in the eastern part of the areas, and consists primarily of tuffaceous conglomerate, lapilli tuff, tuff, and rhyolite lavas. The Yahagi Formation is distributed in the western part of the areas, and consists primarily of tuffaceous conglomerate, sandstone and mudstone, pumice-tuff, and rhyolite lavas. The Hakugindai Lava unconformably covers the rocks of the Ikutahara and Yahagi Formations. In particular, the rocks of the Ikutahara and Yahagi Formations and andesite dikes were affected to various extents by hydrothermal alterations related to the Late Miocene epithermal gold-silver mineralizations of the Muka and Kunihana deposits.Hydrothermal alterations are divided into two stages. The stage I neutral-type alteration zones consist of K-feldspar, illite, interstratified illite/smectite, chlorite, zeolite, and smectite zones, while the stage II acid-type zones include kaolinite, veined 7 A halloysite-kaolinite, and veined smectite-kaolinite zones.Seven ancient slides and the Kanehana-toge slide occurred in hydrothermal alteration zones. The smallestscale Kanehana-toge slide and four intermediate-scale slides were closely related to the veined smectitekaolinite and smectite zones, respectively. Two large- and intermediate-scale slides were also closely related to the smectite zone, to the zeolite zone containing a relatively large amount of smectite, and/or to the kaolinite zone.The largest-scale ancient slide configuration was approximately 1, 450 m in width of displaced material, and approximately 1, 550 m in total length, and was of the “Concave Poly-Hill type” consisting of roughly twelve parts. On the other hand, the smallest-scale slide was approximately 20 m wide and approximately 70 m long. The small- and intermediate-scale slides were of the “Concave Hill type”.These data are useful for evaluating the degree of hazard of slides and for making a hazard map of slides in the hydrothermal alteration zones.