From Dalaman Airport, Havaş airport buses run to and from Marmaris supposedly in conjunction with all arriving and departing flights.
In Marmaris, buses arrive and depart from the main bus terminal (otogar), and stop at Gökova, Köyceğiz, Ortaca (for Dalyan) and Dalaman Town along the way.
Notify the driver, and he will stop at any point you wish.
For the return trip to the airport, the bus departs Marmaris 3 hours before flight departure time.
One-way fare is TL15 for the 90-minute trip to Marmaris.
Havaş airport buses also run to and from Fethiye, the 1-hour trip costing TL10. The schedule is on the Havaş website.
If there are several people in your traveling party, you may save money by renting a car.
—by Tom Brosnahan