The islands are very mountainous, for the most part, except for the rich soiled plains of the Campidano in Sardinia.  The highest peak is Monte Cinto, Corsica, which is around 8890 feet above sea level. The beaches of both Islands are some of the most beautiful in the world, which is also where the Romans tended to colonize themselves.  The abundance of forests in the mountains including pine, beech and evergreen oak, served for both shelter of the natives from the Romans and ship wood for Roman and Punic navies. 

Sardinia's Campidano flatlands were some of the most fertile lands in the Roman Empire. Combined with the cover of the nearby forests it became a staple of the islands for livestock and grain farms, and hence, Sardinia became very important for trade throughout the Empire. 

The Climate

The inlands of the islands were uncharacteristically wet for the Mediterranean.  Nevertheless, the rain was perfect for agriculture, it seemed to help the breeding of disease.  Though, for the most part, on the coasts of both Islands, the climate is fairly mild and typical of the region.  The temperature varies whether you are inland or not, but for the most part the temperature ranges between 60 and 80 degrees.