Silifke, 90 kilometers (56 miles) from Mersin, is a little bit inland, on the site of the acropolis of ancient Seleucia and Colycadnos. The old bridge crossing the Göksu River, the theater and the temple from Roman times are of interest.
To the north of Silifke there is an excellent excursion opportunity, to Uzuncaburc, ancient Diocaeserea. The road up to the magnificent ancient site of Olba - Diocaeserea is lined with large tombs. In the ancient city there are the ruins of the Temple of Zeus, Olbius and the Temple of Tychaion, and numerous arches, theater, Byzantine church and tower. Also Elaiussa Sebaste is one of the most interesting archaeological sites between Silifke and Erdemli. Outside Silifke, on the road to Tasucu is the archaeological museum, while further on Aya Tekla is the tomb and church of Saint Thecla who was the first female martyr.
Tasucu is a pleasant resort town with good accommodations and fine sandy beaches, especially the Aphrodite Beach. The harbor includes regular sea bus services to Girne in the Turkish Republic of Northern Cyprus. Between Silifke and Mersin there is the little fishing village Narlikuyu which you should not pass by without trying the delicious fish by the turquoise bay. In Narlikuyu you can see a Roman mosaic depicting the Three Graces.
Around Narlikuyu an exciting excursion is to Cennet - Cehennem (Heaven and Hell in Turkish), and the Astim Dilek Caves which are deep chasms, one of which has a chapel. They are really fascinating and you will understand why they carry these names once you visit.
60 kilometers (37 miles) west of Mersin there is the ancient city Korykos, which is now the resort town of Kizkalesi, with sandy beaches and camping sites. There are important remains which are symbols of that region like The Castle of Korykos on the beach faces the Kizkalesi (Maiden's Castle in Turkish) which stands on an islet 200 meters (650 feet) offshore. The two castles once used to be joined by a sea wall but now they are separated as the wall submerged. The road from Silifke to Mersin is very enjoyable along the coast; the ancient basilicas, tombs and ruins are on one side of the road and beautiful coves with sandy beaches on the other side.
Ancient Pompeiopolis, founded by Rhodians in 700 BC, provides many remarkable ruins. The modern name of the city is Viransehir and it is 13 kilometers (8 miles) west of Mersin. At Kanlidivane you will see the ruins of the ancient city Kanytelis clinging on the sides of a deep chasm.