Its greatest length is about 141 m., from Cape Drepano in the west to Cape St Andrea in the north-east, and its greatest breadth, from Cape Gata in the south to Cape Kormakiti in the north, reaches 60 m.; while it retains an average width of from 35 to 50 m.
Wide at its entrance, and terminating, on the east, in the Cabo de Gata, the southernmost point of eastern Spain.
Garnets are found in the Sierra de Gata and in the Sierra Nevada fine marble is quarried.
On the west another rough and hilly tract, similar to that which divides it from the Sierra de Guadarrama in the east, separates it from the Sierra de Gata, the westernmost and the lowest of the Spanish sierras belonging to the series.
The Sierra de Gredos has a road across it connecting Avila with Talavera de Ia Reina by the Puerto del Pico; but for the most part there are only bridle-paths across the Gredos and Gata ranges, and no railway crosses either of them, although the line from Plasencia to Salamanca skirts the Sierra de Gredos on the west.