Great question — answering as the UphillTech team:
Having just returned from our trip, I will try to provide a description of how we planned it and how things worked out. When we arrived in Vienna we purchased a topographic map of the Gesause region at a book store. With this in hand, we decided to take a train from Vienna to Gaishorn am See, to the south of the park. The train takes three hours and isn't very expensive, especially if you buy tickets more than a week in advance. In retrospect, I'm not sure Gaishorn was the best choice, because it doesn't have any supermarket, although nearby Trieben has two. But it did have a hotel and some restaurants, and a trail that leads to the Modlinger Hutte , the hut we planned to sleep at for our...
Full answer by Eyal: https://outdoors.stackexchange.com/a/4405 (CC BY-SA 4.0).
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