The stretch of coastline between Rome and Naples has been named after Homer's Odysseus - in Italian 'Ulisse'. The story tells of how Odysseus would dock in this area to draw water from Artekies source to take back to his ships. When Odysseus and his men were fighting against the local population from Sperlonga, he fell in love with the sorceress Circe, which resulted in him staying in these parts for a whole year.
Between the towns of San Felice Circeo and Formia extends a lush protected natural area, which today stands as a neat park system. The flora in the park is typical of the Mediterranean: mixed forest of holm oaks, cork oaks and western arbutus, myrtle, rosemary and heather. There are several routes through the park, which you can read more about here: http://www.parks.it/parco.riviera.ulisse/Eindex.html (English).
Towns like San Felice Circeo, Terracina, Sperlonga, Gaeta, Formia, Minturno are like a string of pearls alternating with long lovely beaches between them. Terracina is an immediately likeable little town, divided between a tumbledown old quarter high on the hill and a lively newer area by the sea. The coast south of Terracina is probably Lazio’s prettiest stretch, the cliff punctured by tiny beaches signposted enticingly from the road. SPERLONGA, built high on a rocky promontory, is a fashionable spot for Roman and Neapolitan families, its whitewashed houses.