For the Romans, the Gallura area situated in northern Sardinia was not an enjoyable destination, rather a resource to exploit.  The Romans needed granite, that incomparable rock representing wealth and the symbol of north-eastern Sardinia.
The Romans used to load the granite for their temples in Rome and all over their empire.  It was a long, hard and complex job.  Nowadays, you might still find marble fragments from columns that fell down during their transportation.  On Cala Spinosa beach, near Santa Teresa, you'll find some of them still intact, finely decorated, jammed among granite blocks and left exactly where the Romans abandoned them centuries ago.
Apparently, the columns of Cala Spinosa were destined to the Pantheon and, in order to make them, the Romans stayed on the island for a long period of time, as evidenced by the presence of a castrum on the Capo Testa promontory.
If, during the Roman Age, granite was essential to make the imperial monuments, at the end of the second millennium it is still essential to build the skyscrapers' façades in Sidney and Boston.
The Marmorata and Santa Teresa di Gallura islands today represent two important and sought-after tourist destinations.  One of the most important attractions are the rare animal and plant species living in the area such as the Pediagra lizard, usually hidden among succulent plants and almost glued to the rocks in order to resist against the constantly blowing wind.
The islands are also a very pleasant environment for cormorants and seagulls that choose the area for nesting and laying their eggs.  Thousands and thousands of eggs represent natural food for the numerous rats living on the Marmorata islands.  These rodents are afraid of humans and quite rarely they come in contact with them.
The beaches
The Marmorata islands are quite small, almost set among the rocks.  The sand is thicker than that of Rena Majore beach in Santa Teresa.  But the beaches here are a real paradise, with incredibly clean waters and by extraordinarily shaped granite.
The wonderful sea protected form the north-east and north winds, is not only a tourist resource but also an inexhaustible fish reservoir.
The seabed is also well-known for the presence of numerous wreckages, mixed in with the thick vegetation, granite, fish and molluscs.  Divers use the wreckages in order to orient themselves.
Santa Teresa village is important not only for its beautiful and natural surroundings but also because it's one of the few centres in Sardinia built following an urban plan.  It was drawn up in 1820 and included a succession of perpendicular streets headed by two main squares.  Vittorio Emanuele I chose the village's name in honour of his wife.
But there is also evidence of Pisan domination, such as the castle built in Porto Longone.  Around the walls of the castle rose a small village, very important for trade with close-by Corsica.  Unfortunately it was destroyed by the Aragonese in 1418 and the area became smugglers' territory.
Nowadays, Santa Teresa represents a union, unfortunately not always successful, between the need to preserve the natural resources and the need to earn nourishment from them.

There are innumerable, beautiful tourist destinations including the San Pasquale suburb, from where a scenic route lets us admire an extraordinary view of the sea; the Coluccia peninsula, mentioned by Giuseppe Garibaldi during his stay in Sardinia; the Capo Testa promontory, where the smooth granite has unusual shapes and strange colours and the famous Valle della Luna (Moon Valley), a massive fault widened by erosion in past centuries.