The Hanaore fault is a right-lateral strike-slip active fault about 48km long in central Japan. We carried out comprehensive surveys including trench excavations on the Hanaore fault to evaluate the seismic risk of the highly populated area, such as Kyoto City, along this fault. Three trenches were excavated on the fault. On the exposure of the northernmost Tochudani trench, a fault cutting fluvial sediments and humic soil beds appeared. The youngest age of displaced sediments is 460±60 ¹⁴C yBP, and the sediments covering the fault is 360±60 ¹⁴C yBP. This faulting event may be correlated to the historical 1662 Kambun earthquake. The southernmost Imadegawa trench was excavated on the road in the urban area of Kyoto City. A thrust fault cutting humic soil with pottery fragments of the Late Jomon period (about 3, 500 years ago) was observed on the trench walls. It was difficult to detect the age of the last faulting event due to lack of younger sediments and artificial modifications of the surficial materials. However, the southern part of the fault might not move during the 1662 earthquake because the damage in this area was much less than in along the northern and middle part of the fault. The historical documents recorded that the land along the Mikata fault which is located at the north of the Hanaore fault was uplifted, and the land along the western shoreline of Lake Biwa where is the east of the Hanaore fault was subsided during the 1662 earthquake. This means that the 1662 earthquake might be a multi-segment event caused by these three faults, the Mikata fault, the northern part of the Hanaore fault, and the faults along the western shoreline of Lake Biwa.

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