My girlfriend and I holidayed in Calis Beach (a beach resort close to the town of Fethiye) in April 2010.
The resort was remarkably quiet at the time of our visit. We were there just before the summer season started and arrived on one of the first flights after the lifting of a flight ban caused by volcanic ash clouds resulting from the eruption of a volcano in Iceland.
As this video shows, the vast beach and seafront promenade was practically empty. We often found ourselves eating in near-empty restaurants.
I'm sure Calis Beach is a much busier place in the height of summer...but we really enjoyed its peaceful off-season atmosphere!