At the end of the day in Kas, you can collapse on a lounge at one of the cliff-side "beaches" to the southeast of town, where you're only a coral stone's throw away from a dip in some of the bluest and unspoiled waters this close to a major town. Küçükçakil Beach ("small pebble beach") sits to the east of the marina, protected by an outcropping of rocks upon which a number of private establishments (mostly the hotels that front the coastline) provide beach lounges and umbrellas. The rocky coast forms a small inlet, into which crazy local kids dive off the low craggy rocks. Farther out about 800m (1/2 mile) is Büyükçakil, or "large pebble," Beach, a small but amazing stretch of waterfront embraced and protected on three sides by low hills covered in Mediterranean brush. The beach is free and informal, but there are one or two basic facilities for showering and such, as well as lounge chairs for rent and a snack bar.
There's also the bay of Limangazi located on the other side of the bay and accessible only by boat. Ask a local fisherman or boat captain how much he's asking to take you there (and hopefully, back).
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.