Some Greek writers were impressed by them, Dyodorus Siculus (early 1st century bc) for example wrote about them:

"Near Cyrnus (Corsica) there is an island called Sardinia, about the size of Sicily, inhabited by barbarians called Iolai and it is thought that these descend from the men who settled there with Iolaus and the Thespiades. he was engaged in the accomplishment of his famous "labors", he had many sons by the daughters of Thespius, these were sent to Sardinia by the same Heracles, respecting certain oracles, together with a remarkable force composed by Greeks and barbarians, in order to establish a colony. Iolaus, nephew of Heracles, was in charge of the expedition and taking possession of the island founded some important cities and after having divided the lands in lots called the people of the colony "Iolei", from its name. Then Iolaus, constituted the colony, sent to call from Sicily Daedalus, and he built great works that remained until our times (about 90 BC) called, by their architect Dedalea. He also built large and lavish gymnasiums and set up courts, and temples for the gods and all the other things that lead to prosperity. He called Iolaei the inhabitants by imposing their name on himself, with the agreement of the Tespiadi who gave him this privilege as a father.He built great works still standing today known as Dedalaia and everything that could help to make human life happy, even today the memories remain. The oracle that spoke of the colony also contained the promise that everyone who participated in the business would keep freedom forever."

Pseudo-Aristoteles, 2nd century AD: "It is said that on the island of Sardinia there are buildings modeled according to the ancient Hellenic tradition, and many other splendid buildings, and buildings with domed vault with extraordinary proportions ratio. It is believed that these works were raised by Iolaus son of Ificle in the time when, taking with him the Tespiadi sons of Heracles, he transferred the colony to lead it away from their places of origin to those districts, since he procured these for the relatives of Heracles , to which any land was located to the West believed belonged [...]. They tell then that Sardinia has been, in ancient times, prosperous and dispensing of every product: in fact they tell that Aristeo, who - it is still said - in his time had been the most expert among men in the art of cultivating the fields, were the lord in these places; before Aristeo these places were occupied by many and large birds [...]"