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(1870–1968). Someşul Mic River has recorded in the last 4 decades important changes in both flow regime and channel morphologies, following major hydrotechnic works that started in the early 1970s. In order to understand the river’s adjustments to these new conditions of evolution, a first necessary step is the deciphering of the river’s behavior in undisturbed conditions. In this study we have analyzed the morphometric characteristics of the river channel, in order to establish specific morphologic types, as well as patterns of their change. Four sets of topographic maps were used, with scales ranging between 1: 28.800 and 1: 25.000, covering a period of nearly 100 years: 1870, 1890, 1956, and 1968. The analyzed morphometric parameters were the length and width of the channel, sinuosity index, braiding index, and the horizontal shift in the position of the channel. The main characteristic of the river is the alternation of sinuous, meandering and braiding channels, induced by local tectonics and lateral supply of sediments; characteristic which is conserved over the entire suited time interval. When analyzed in more detail, we observe that three different situations occur along the river: 1) stability, characterizing sinuous sectors, 2) decrease of the channel’s dynamic character (straightening and shortening of the channel through meander neck cut-off), and 3) increase of the dynamic character (evolution of the meanders towards higher complexity); the last two cases being characteristic for the meandering and braiding sectors of the river.