From Rosendal (municipality Kvinnherad/Hordaland) there is a road into the Hattebergdalen. From a distance you already have a good view on the fall. The road end at the river Ringerike. As far I can see there is trail starting south of the river which leads up the mountain to the top of the fall.
A little bit further towards Sunndal you will find one of the widest waterfalls of Norway, the Furebergsfossen. When time left also get hiking in the Bonhusdalen/Bondhusvatnet where you can find several waterfalls: Kroksfossen and the Brufossen.