Arabia Terra is a large upland region in the north of Mars in that lies mostly in the Arabia quadrangle. It is densely cratered and heavily eroded. This battered topography indicates great age, and Arabia Terra is presumed to be one of the oldest terrains on the planet. It covers as much as 4500 kilometers at its longest extent, centered roughly at 19°47′N 30°00′E / 19.79°N 30°E / 19.79; 30^[1]Coordinates: 19°47′N 30°00′E / 19.79°N 30°E / 19.79; 30^[1] with its eastern and southern regions rising 4 kilometers above the north-west. Alongside its many craters, canyons wind through the Arabia Terra, many emptying into the large Northern lowlands of the planet, which borders Arabia Terra to the north.

Arabia contains many interesting features. There are some good examples of pedestal craters in the area. A pedestal crater has its ejecta above the surrounding terrain, often forming a steep cliff. The ejecta forms a resistant layer that protects the underlying material from erosion.^[2] Mounds and buttes on the floor of some craters display many layers. The layers may have formed by volcanic processes, by wind, or by underwater deposition.^[3][4] Dark Slope Streaks have been observed in Tikhonravov Basin, a large eroded crater. The streaks appear on steep slopes and change over time. At first they are dark, then turn a lighter color, probably by the deposition of fine, light colored dust from the atmosphere.^[5]These streaks are thought to form by dust moving downslope in a way similar to snow avalanches on Earth.^[6]

Layers in Tikonravev Crater in Arabia, as seen by Mars Global Surveyor (MGS). Layers may form from volcanoes, the wind, or by deposition under water. The craters on the left are pedestal craters. Some researchers believe this crater once held a massive lake.	Tikonravev Crater Floor, as seen by Mars Global Surveyor. Click on image to see dark slope streaks and layers.	Layers in Monument Valley. These are accepted as being formed, at least in part, by water deposition. Since Mars contains similar layers, water remains as a major cause of layering on Mars.	Tikhonravov Basin Streaks, as seen by HiRISE. Scale bar is 500 meters long
Pasteur Crater Floor, as seen by HiRISE. The scale bar is 1,000 meters long	Henry Crater Mound, as seen by HiRISE. The scale bar is 500 meters long	Crater in the middle of Cassini, as seen by HiRISE. Layers may have been deposited under water since it is believed that Cassini once held a giant lake.

Arabia Terra was named in 1979 after a corresponding albedo feature on a map by Giovanni Schiaparelli, who named it in turn after the Arabian peninsula.

Research on the region was undertaken in 1997 and the individuality of the province better defined.^[7] An equatorial belt was noted with a crater age distinctly younger than the northern part of the province and of Noachis Terra to the south. This was interpreted as an "incipient back-arc system" provoked by the subduction of Mars lowlands under Arabia Terra during Noachian times. Regional fracture patterns were also explained in this manner, and the rotational instability of the planet as a cause was not supported.

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