I was skiing in Zell Am Zee in February and it was absolutely beautiful I'm led to believe it's a very popular location in the summer, you can fly into Salzburg and then get the train right to the center of town it takes about 90 mins. Zell am Zee is on the edge of a beautiful lake you can stay down around there and enjoy the activities or there are cable cars that take you up the mountains where you can go walking and stop off at little bars dotted around the mountains with the most amazing views. I stayed in the Gruner Baum and while it's fairly basic the food was good and the owner/staff were great. It was my first time in Austria, I loved it and would go again.
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