Day Trips ( Excursions) you can book direct or through any agent in Marmaris
Scuba Diving, Sea Kayaking, Mountain Biking, Canyonning Snorkelling, Horse Riding, Water Rafting. Boat trips, Fishing Trips, Jeep Safari, Village Tours, Bar Crawl, Talk of the Town (dinner with entertainment), Turkish night (dinner with entertainment, Rhodes, Ephesus (Ancient City), Pamukkale (cotton castle, wonder of world), Dalyan Mud Bathsand Caunos ruins, Turkish Bath, Bar Crawl (Bar Street). Often booking direct will cut out the middlemen agents and save you money. (google the activity and Marmaris and check out a couple of companies)
Day trips that you can do on your own
Walking on the prominade to Icmeler or Marmaris, visiting local markets, visiting a mosque, catching local transport or even better hiring a car ( if you are an experienced driver) to Turunç, Akyaka, Datça, Mesudiye, Palamutbükü, Ovabükü, Söğütlü, Bayır, Orhaniye, Selimiye, or Bozburun villages. Catching a water taxi to Turunç or Kumlubük for a day out. ( pack your beach bag ). You can do many of the above day trips under your own steam.
Must have a Turkish Village Breakfast before you leave in a reputable restaurant. If you have kids Asparan restaurant which has a childrens playground in Degirmenyanı is highly reccomended. Towards Çamlı village there are a few of these breakfast experts like Çınar, Saklıgöl, Azmakbaşı or Halil Restaurants.If you would like something more private than a restuarant try Sakız Villa in Çetibeli. Beautiful villa with a swimming pool serves you the best breakfast and makes you feel at home.
Most amazing views and wonderful day trips in the area : Datça, Oranhiye, Selimye, Bozburun. You can check Marmaris municipality web site (English version) : www.marmaris.bel.tr and click on 'around Marmaris'. Also you may see the places around Marmaris in details from Complete Marmaris Travel Guide page.