Gytheio (, ) or Gythio, also the ancient Gythium or Gytheion (), is a town on the eastern shore of the Mani Peninsula, and a former municipality in Laconia, Peloponnese, Greece. Since the 2011 local government reform it is part of the municipality East Mani, of which it is a municipal unit. The municipal unit has an area of 197.313 km2. It was the seaport of Sparta, some north. Gytheio is the site of ancient Cranae, a tiny island where according to legend Paris of Troy and Helen from Sparta spent their first night together before departing for Troy, thus igniting the Trojan War. Gytheio used to be an important port until it was destroyed in 4th century AD, possibly by an earthquake. Even thereafter its strategic location gave Gytheio a significant role in Maniot history. Today it is the largest and most important town in Mani. It is also the seat of the municipality of East Mani. Historical population Geography Gytheio is located in the northeastern corner of the Mani Peninsula and lies on the northwestern end of the Laconian Gulf. Gytheio was built on a hill called Koumaros or Laryssio in one of the most fertile areas in Mani, near the mouth of the Gythium River, which is usually dry and has been nicknamed Xerias "dry river"; today, most of the Xerias is covered by Ermou Avenue. Directly north and visible from the harbor is Profitis Ilias, the ultra-prominent peak of Taygetus, the mountain range whose spine juts southward into the Mediterranean Sea and forms the Mani Peninsula. On the ridgeline running south from Profitis Ilias sits the Monastery of Panayia Yiatrissa overlooking the valley toward Gytheio; the E4 hiking path connects the three, running south from Profitis Ilias, passing by the monastery, and leading to Gytheio. Northeast of Gytheio is the delta of the Evrotas River. Offshore are several small islands; the most important of these islands is Cranae, on which sits the Tzannetakis Tower (now the Historical and Cultural museum of Mani) and a lighthouse built of solid marble. Today Cranae is connected to the mainland by a causeway. Approximately 5 km (3 mi) southwest is a passageway to the deeper Mani, historically guarded by Castle Passavas (now in ruins), which towers over the site of ancient Las. Further west is the historic city of Areopoli and the Caves of Diros, which are important tourist attractions.