Fluvial terraces along the Duero River in Spain were studied to understand how the landscape evolved when the basin opened up. By analyzing the age of different terraces using a special isotope, researchers found that the terraces formed during the Pleistocene period. The rate of erosion in the basin increased during the Early Pleistocene, indicating faster landscape changes. The erosion rates were higher near the opening of the basin compared to further upstream, showing how the erosion spread backwards from the opening site. This study provides insights into how rivers and landscapes respond to changes in their surroundings over time.