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The Nobi Plain, north of Ise Bay, Japan, is a Holocene fluvialcoastal lowland formed mainly by the Kiso, Nagara, and Ibi rivers. This paper introduces the late Pleistocene to Holocene sedimentary sequence and landforms of the plain. The landforms are classified into low-gradient alluvial fans, floodplains, and deltas using aerial photograph interpretation. The stratigraphy of the plain since around the Last Glacial Maximum (LGM) is divided from bottom to top into First Gravel, the Nobi Formation, and the Nan yo Formation mainly on the basis of lithofacies by analyzing borehole columns. Many valuable data have been accumulated by detailed sediment facies analyses and radiocarbon dating of borehole core sediments, especially during the last years. These data have enabled us to understand the evolution of the sedimentary sequence in response to sea-level change during the last , years at a millennial timescale. However, information for the interval between the LGM and the Younger Dryas is very limited. Reconstruction of the three-dimensional stratigraphic architecture of incised-valley fills and the estimation of sediment storage of the deltaic deposits were performed by analyzing existing borehole columns and radiocarbon ages and using a geographic information system. Sediment storage increased considerably after cal BP probably as a result of the increase in sediment production accompanying human activity in the drainage basin. Recent human activities in the drainage basin have caused marked changes in its aqueous and sedimentary environments. The changes are visible in the form of features such as land subsidence, local riverbed scouring, and ecological changes.

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