Today's Red Sea; Saba was part of southern Arabian Peninsula.
The Sinus Sabaeus quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey Astrogeology Research Program. It is also referred to as MC-20 The Sinus Sabaeus quadrangle covers the area from 315° to 360° west longitude and 0° to 30° degrees south latitude on Mars. It contains Schiaparelli, a large, easily visible crater that sits close to the equator. (wikipedia entry)
A albedo feature is an area which shows a contrast in brightness or darkness (albedo) with adjacent areas. On Mars they are named after names from classical mythology assigned by Schiaparelli and Antoniadi.