亀の瀬Kame-no-Se 

亀の瀬地すべりり対策工事を見学
Kame-no-Se is located at a constriction where the Yamato River is about to drain into the Osaka Plain near the border between Osaka and Nara prefectures.
National Route 25 and the JR Yamato Line run across the Kame-no-Se area, making it an important transportation hub.
Kame-no-Se has long been feared as an area where landslides occur, and one of the world's largest "landslide prevention works" was carried out in this area.