I thought it might be a rip off (think it was ~105 CzK each) - also keep your change for the bathroom think that was 5Czk - but the view from the top was good. You do need to get above the trees to see Prague from the hill and this takes care of that.
We walked up - the elevator is extra - the walk is good because you can take pictures without the glass in the way (some windows open, but if there are many people you will have to wait to take a picture).
Also note that if you are going to the hill the tram may not be running - perhaps you can check online, but we didn't think to check and the funicular was closed for a few weeks.
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