Continental-scale hydrologic routing models, also known as macrohydrological routing models, have evolved considerably in the past few years. As the models have become more sophisticated, they have represented a variety of new processes and expanded their data requirements-either as input data or as validation for the model output. This paper presents a new data set of large-scale hydrological river flow routing parameters for the Amazon and Tocantins basins. Part of this data set was required by the development of the continental-scale hydrological routing model HYDRA and its application to the Amazon Basin. HYDRA represents phenomenalike floods, backwater effects, and seasonal hydrograph much more realistically than the previous generation of macrohydrological routing models. The data set contains data on (1) river network at 5-min (~9 km) resolution, (2) time series of monthly means of river discharge and river stage for 122 fluviometric stations spread throughout the basin, (3) sinuosity of each of the main rivers measured at 111 river sections in the basin, and (4) depth to the water table and transmissivity of the aquifer derived from measurements taken at 81 points throughout the basin.