If ruins are not your thing you can easily hop a dolmuş 10 kilometers north from Antalya to visit the Upper Düden Waterfall, set in a pleasant park with picnic area and petting zoo.
The falls are insanely busy over summer weekends so time a visit for midweek after mid-September (when Turkish schools reopen) if possible.
Don’t confuse the upper falls with the lower ones (Asağı Düden Şelalesi) which can be found down on Lara Beach in Antalya.