The ecoregion covers the interior basins of Iberia's main rivers – the Douro, Tagus, Guadiana, Guadalquivir, and Ebro.

[2] Olive-carob woodlands and maquis are common in the southern portion of the ecoregion, and in canyons in the northern Douro and Tagus basins.

[2] Areas of the southeast and Ebro valley with limestone, marl, and gypsum-derived soils are home a mosaic landscape, with mixed forest of Aleppo pine (Pinus halepensis) and holly oak (Quercus coccifera), open juniper woodlands of Juniperus thurifera and Juniperus phoenicea, steppe grasslands with Stipa tenacissima and Lygeum spartum, and low shrublands with Artemisia herba-alba, Thymelaea hirsuta, Ononis tridentata, Helianthemum squamatum, and Thymus mastigophorus.

[2] Extensive seasonally-flooded saline wetlands of Suaeda fruticosa, Microcnemum coralloides, Aizoanthemum hispanicum, Arthrocnemum glaucum, and Limonium ovalifolium cover areas with poor drainage.

Dehesas support wildlife as well as livestock and crops, and forest products like cork, honey, mushrooms, and wild game.

Year-round resident birds include the Spanish imperial eagle (Aquila adalberti) and great bustard (Otis tarda).