The narrow strait between Mykonos and Delos spans less than four nautical miles, yet it separates the modern resort island from one of antiquity's most venerated sanctuaries. Delos served as the mythological birthplace of Apollo and Artemis, and by the seventh century BCE it had become the political and religious heart of the Cyclades, hosting the Delian League treasury and drawing pilgrims from across the Hellenic world. The island's population swelled to thirty thousand during its Hellenistic zenith, supported by a harbor quarter lined with warehouses and a residential district where merchants from Egypt, Syria, and Italy built townhouses adorned with intricate floor mosaics. Today the uninhabited island preserves one of the Mediterranean's most complete archaeological landscapes. The ruins occupy roughly forty hectares, beginning at the Sacred Harbor where ancient triremes once moored and extending upward to Mount Kynthos, the island's modest summit. The Terrace of the Lions—five marble sentinels carved from Naxian stone in the seventh century BCE—remains the site's most recognizable feature, though the original sixteen guardians have weathered, been relocated, or vanished over twenty-six centuries. The museum adjacent to the landing pier houses a collection spanning the Mycenaean period through Roman occupation, including the archaic kouros statues and Hellenistic theatrical masks recovered from residential excavations. The boat crossing from Mykonos departs daily during the main season, with services concentrated in the morning hours to align with the archaeological site's opening schedule. The twenty-to-thirty-minute journey passes the uninhabited islet of Rhenia, Delos's ancient necropolis, where the Athenians mandated all burials take place to preserve the sacred island's ritual purity. Ferry operators run diesel launches and small catamarans from the Old Port jetty in Mykonos Town, with most services including return passage timed to allow three to four hours on-site. Guided crossings often combine the ferry transfer with an archaeologist-led walk through the Sanctuary of Apollo, the ancient theater, and the residential quarter, where the House of Dionysus and the House of Cleopatra retain their original mosaic floors. Full-day excursions extend the itinerary to include a swim stop at Rhenia's southern beaches and a midday meal aboard the vessel, though these longer cruises typically dock at Delos later in the morning and allow less time for independent exploration of the ruins.