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Palaeofloods in the Whanganui River, North Island, New Zealand are investigated using floodplain sedimentary archives at two locations in the lower Whanganui catchment. The ca. AD 232 Taupo volcanic eruption transformed the lower valley of the Whanganui River, emplacing a substantial volume of volcanogenic mass flow material and providing a new starting point for subsequent alluvial sedimentation. At Atene a high–resolution archive of flood sediments is preserved in a valley meander cutoff in the lower reaches of the Whanganui Gorge, where a ~9 m core was extracted. At Crowley House further down valley, two ~5 m cores were also extracted from a terrace-confined floodplain. Organic material from these cores allows the timing of floods at these sites to be constrained using 11 radiocarbon dates (ten from Atene, one from Crowley House). Flood magnitudes are reconstructed using XRF core-scanned …