Linz is not a city I would go out of way to visit. If you happen to be traveling down Danube or driving through, I would go see it. The main square isn't the greatest although it does have little outdoor Easter markets if you happen to go in April. Linz tort is also apprently a highlight, but it was just a good tort, not life changing.
If you are Linz, get your feet over to the Meriendom gothic church (spire is visible from the city center.
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