Strangely - we first visited Oludeniz when we were students in the early 80's. Caught a dolmus from Marmaris, stopped off in a small town called Fethiye to see the tombs and then on to Oludeiz where there was one hotel (I think?) and a camp site. However, the spit at the lagoon was really busy - as bad as now - as there were lots of coach tours there.