The ferry ride into and the bus ride out of the fjord are the major highlights. The seven sisters waterfall is simple breathtaking, even on a cloudy day. The bus stops on one of the mountain slopes for some photo ops, where you get an bird's-eye view of the fjord and the waterfall.
I would highly recommend taking the bus out of the fjord as there is plenty of other stunning scenery along the way you wouldn't get to see if you were to take the ferry alone.
There is no time to climb up the mountain top within a day. If you really want to do that, just stay overnight in the fjord. But make sure you check that the weather is clear because it puzzles me how English weather has worse reputation. Just note that there is nothing much in the village - only a couple of souvenir shops, a couple of small hotels and a few holiday homes.
That said, it is definitely a must-visit in Norway.
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