Sperlonga was an ancient Roman resort: Emperor Tiberius built here a famous villa, including one of the grottoes (Latin: speluncae) which gave the name to the town.

After the fall of the Western Empire, in the 6th century, the ruins of the Imperial residence served as refuge for local people. Later the population began to move to the nearby promontory of St. Magnus, in order to escape the unhealthful marshes and the Saracen attacks. The danger posed by the Saracens is made clear by the presence of many watchtowers all along the coast to Gaeta. In 1534 the small centre was destroyed by Barbarossa.

In the 18th and 19th centuries Sperlonga recovered and acquired some noble residences, and agriculture flourished. However, the touristic expansion occurred only after the opening of the coastal road Terracina-Gaeta (the via Flacca) in 1957.

 

wikipedia: http://en.wikipedia.org/wiki/Sperlonga