What the city is best for
Side should be planned by area, travel time and what you actually want to do. It works especially well for beach, family, history, resort and calm stay. The main anchors are Apollo Temple, Side ancient city, harbour, Manavgat Waterfall and East and West beaches, but the value of the trip depends heavily on where you stay and how you structure the days.
The most useful bases are Side old town for atmosphere, Kumköy/Evrenseki for resort hotels, Sorgun for calmer nature feel and Manavgat for local town access. Choose short access to what you will do most, not just the lowest hotel price. For short stays, a better location often saves both time and transport.