A rental car is the best way, hiring a tour agency to drive you there would work, but shop around for best price. Taxi would cost too much, buses are iffy. By car will take about 2-1/2 to 3-1/2 hours. Take a map or find a map is a must. The scenic way from Kayseri is over the Erciyes mountain to Develi and follow the signs to Yahyali. Through Yahyali east to a small town Dikme, turn there and you should start seeing signs for Kapuzbasi Selale. Plenty of places to take photos.
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