The Aravali mountain ranges that run from Delhi to Gujarat cut through the State almost vertically. The Aravali ranges divide the State through south-east and north-west. The north-west region covering two-thirds of the state consist mostly of a series of sand dunes. Bikaner, Jaisalmer, Jodhpur and part of the Jhunjhunu districts form” part of this region. The eastern region has large fertile tracts.

The Northwestern thorn scrub forests lie in a band around the Thar Desert, between the desert and the Aravallis. This region receives less than 750 mm of rain in an average year, and summer temperatures can exceed 45º C in the summer months, and drop below freezing in the winter. The Godwar, Marwar, and Shekhawati regions lie in the thorn scrub forest zone, along with the city of Jodhpur.

The Luni River and its tributaries are the major river system of Godwar and Marwar Regions, draining the western slopes of the Aravallis and emptying southwest into the great Rann of Kutch wetland in neighboring Gujarat. The Ghaggar River, which originates in Haryana, is an intermittent stream that disappears into the sands of the Thar Desert in the northern corner of the state.

The Aravalli Range and the lands to the east and southeast of the range are generally more fertile and better watered. This region is home to the Kathiarbar-Gir dry deciduous forests ecoregion, with tropical dry broadleaf forests that include teak, Acacia, and other trees. The hilly Vagad region lies in southernmost Rajasthan, on the border with Gujarat.

With the exception of Mount Abu, Vagad is the wettest region in Rajasthan, and the most heavily forested. North of Vagad lies the Mewar region, home to the cities of Udaipur and Chittaurgarh. The Hadoti region lies to the southeast, on the border with Madhya Pradesh. North of Hadoti and Mewar is the Dhundhar region, home to the state capital of Jaipur. Mewat, the easternmost region of Rajasthan, borders Haryana and Uttar Pradesh. Eastern and southeastern Rajasthan is drained by the Banas and Chambal rivers, tributaries of the Ganges.