From Mykonos, organized guided and unguided excursions leave starting about 8:30am about four times a day Tuesday through Sunday at the harbor's west end. Every travel agency in town advertises its Delos excursions (some with guides). Individual caique owners also have signs stating their prices and schedules. The trip takes about 30 minutes and costs about 10€ round-trip; as long as you return with the boat that brought you, you can (space available) decide which return trip you want to take when you've had enough. The last boat for Mykonos usually leaves by 4pm. The site is closed on Mondays.
Warning: If you're heading to Delos just to see the Avenue of the Lions, double-check to see if the lions are in place. Recent restoration activity and staff cutbacks have had caused some of the noble beasts to have to endure the indignity of being put into storage. Some replicas have been substituted on the site.
Carpe Diem -- Heavy seas can suddenly prevent boats docking at Delos. Follow the advice of the Roman poet Horace and carpe diem (seize the day). If you want to visit Delos, come here as soon as possible; if you decide to save your visit here for your last day in the area, rough seas may leave you stranded ashore.
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.