Polfossen is rather a large rapid than a waterfall. You can visit it if you drive nearby. There's a budget hotel near the waterfall, but no other infrastructure, and the nearest town is located 30 minutes away. In addition to the waterfall there are fairly dense forests in the area. We walked there and even managed to find a mushroom :)
Getting there: It's difficult to get to the waterfall by public transport. It's located on the road between Lom and Stryn / Geiranger. There are several buses between Lom and Stryn, find the schedule here. At the same website you can also find buses from Oslo to Lom or Stryn.