1 Ma of long-term landscape reconstruction of the River Tagus (Iberia): a record of tectonics, climatic changes, sea-level fluctuations and past human occupation.

The Tagus Basin, located in the central Iberian Peninsula and shared by Spain and Portugal, represents a pivotal region for understanding the interplay between paleo-environmental processes and past human living and adaption. The Tagus River, the longest in the Iberian Peninsula, originates from the transition of the Cenozoic basins from an endorheic drainage system to an exorheic system flowing into the Atlantic Ocean in the Plio-Pleistocene (Solè Sabaris, 1951; Vaudour, 1979; Silva et al., 1988; Pérez-González, 1994; Cunha et al., 2008; Benito-Calvo and Pérez-González, 2010; Silva et al., 2017; Karampaglidis et al.,2020).  In the Tagus Basin, following the transition, the capture and dissection from the Atlantic drainage system resulted in the formation of a Quaternary staircase fluvial system, comprising up to twelve levels in the western part of the MCB, up to twenty-three terrace levels in the eastern part of the MCB, and up to six levels in the Lower Tajo Basin (Pérez-González, 1994; Cunha et al., 2008). In this terrace sequence is preserved a unique and fundamental archive for the European Paleolithic sites (Santonja, M. & Villa, P., 2006; Rubio-Jara & Panera., 2019). The location of the Tagus Basin constitutes a strategic spot in the centre of the Iberian Peninsula and preserve one of the largest assemblages of Pleistocene sites in Europe (Santonja & Querol, 1978; Panera & Rubio-Jara, 2002; Rubio-Jara et al., 2016; Rubio-Jara & Panera, 2019). Research on the Pleistocene and the Palaeolithic of the Tagus Basin has started since 1862 and has continued up to now with plentiful discoveries of Pleistocene lithic industry and faunal remains (Verneuil & Lartet, 1863; De Prado, 1864; Obermaier 1916; 1925; Santonja & Querol, 1978; Santonja et al., 1980; Cobo et al., 1980; Gamazo et al., 1983; Querol, 1984; Rus and Vega, 1984; Pérez González & Manuel Santonja, 2000; Santonja & Pérez González, 2001; Vega Toscano & Santonja Gómez, 2002; Panera & Rubio-Jara, 2002; Baena & Baquedano, 2004; Silva et al., 2008; Panera, 2009; Baena et al., 2010; De los Arcos et al., 2010; López-Recio et al., 2010; Manzano et al., 2010; Santonja Gómez, 2010; Rubio-Jara, 2011; Pérez González & Manuel Santonja, 2014; Rubio-Jara & Panera, 2019).

However, further geomorphological studies are essential to unravel the dynamics of sedimentation, erosion, formation, alteration, and preservation of the Paleolithic record, as well as the environmental contexts in which hominins lived and interacted. The geological setting of the Tagus Basin makes it an ideal natural laboratory for examining how tectonic activity, lithological diversity, and climatic fluctuations have shaped terrain formation and landscape evolution. Comprehensive geomorphological mapping of major landforms, combined with morpho-sedimentary analyses and advanced dating techniques will establish a robust geospatial-temporal framework. This framework will serve as a unified database, facilitating an understanding of the primary mechanisms driving landscape evolution over the last 1 Ma. Moreover, it will provide critical insights into the processes of sedimentation, erosion, and preservation of the Paleolithic record, offering a detailed perspective on the environmental conditions that shaped hominin behavior and adaptation in this region.