Six examples of river sandstone bodies are described from well exposed sections of Oligocene and Miocene age in the Ebro Basin, northern Spain. Three of these are of ribbon form, varying in cross-section from 10 m wide × 2 m high to 20 m wide × 9 m high. In plan these ribbons vary from straight to highly sinuous. The sandstone bodies, in two cases, are multi-storey, clearly demonstrating a series of vertical building episodes. The fourth sandstone body may have a ribbon or sheet geometry, and is of special interest because it demonstrates lateral building by a laterally migrating channel, as well as some vertical building. The fifth and sixth sandstone bodies are of sheet geometry, and demonstrate lateral migration of channels and depositional surfaces. Factors that appear to be most important in determining whether a river migrates laterally or remains stable laterally are: (1) river mean flow strength, (2) bank strength, (3) flood periodicity and duration, (4) vertical movement of the alluvial area.

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River systems of part of the Himalayan foreland, northern Bihar plains, India, are described in terms of their channel morphology, hydrology and suspended sediment characteristics. A simple classification of the river systems based mainly on the source area characteristics is proposed: (i) mountain‐fed, (ii) foothills‐fed, (iii) plains‐fed and (iv) mixed‐fed rivers. Distinct differences are noted between these classes of river systems. Most rivers show evidence of channel movement, mainly by avulsion, but cut‐offs also occur locally. The mountain‐fed rivers are characterized by very high discharge and low suspended sediment concentration and the plains‐fed rivers have relatively low discharge and high suspended sediment concentration. The foothill‐fed rivers have moderate values of discharge and suspended sediment concentration. The mountain‐fed rivers have built megafans of large extent, whereas the foothills‐fed and plains‐fed rivers have formed muddy interfan areas. Semi‐quantitative estimates of water and sediment flux suggest that about 99·9% of the mass transfer into the plains is water, with the remaining 0·1% being sediment, and that 10% of the latter (0·01% of the total) is retained in the basin, the remainder being transferred to the Bengal Fan.