olu deniz is the beach and lagoon area with a selection of bars, restaurants etc where as hisaronu is inland about 1.5 - 2 miles but theres more restaurants , shops etc there, so really depends whether you prefer to be in walking distance of the beach or not. personally i prefer olu deniz as i love the scenery and prefer to be nearer to the beach and lagoon. dolmuses run very regularly between the 2 and its only 5 mins up a steep hill , not sure what time the last is, but taxis shouldnt be too dear. i think hisaronu might be lively for night time. most of the hotels in olu deniz have lovely views, belcekiz beach has excellent reviews and is right next to the beach

all the real nite life is up in hisaronu and ovacik but as elliemeg says its all down to where you want to be the scenery at olu is breath taking to say the least that is why it is turkeys most photographed beach
but me personally i prefer the cooler air up on the plato of hisaronu and journey down to the many beach areas of olu

We are staying in Ovacik and believe we can catch a Dolmus to Olu. I know about the famous Blue Lagoon, but from the last post it looks like there are many beaches - are they easy to come by, and does the bus stop at various beaches?

the dolmus stops at the bottom walk to the right and you will see the olu deniz conservation beach go to theright of that and walk round you come to the lagoon beaches

The Buzz bar and Carusoes in Olu Deniz are great venues at night. I think they are a bit more sophosticated than some of the bars in Hisaronu, which can be a bit Karaoke and waitors dancing on bars.

http://www.buzzbeachbar.com/oludeniz_buzz_beach_bar_photos.html

http://www.oludenizbeach.com/nightclubs.html

I think if you are looking for finesse OLU DENIZ is the place!