The starting point for the hike to Nidersee is Arnisee (UR). This can be reached by cable car either from Amsteg or from Intschi (www.arnisee.ch). It is best to follow one of the signposts in the direction of Leutschachhütte. It is open from mid-June to mid-October. The hut is also a perfect place to stay overnight. 
The hike starts easy and you can enjoy views over Arnisee. Soon it will get steeper but still it's a fascinating hike along the little river in between flower fields and grazing cows. 
After about 1:40 hrs you'll reach a very steep ascent and that was very demanding since it was super hot. However, you'll be rewarded with a fantastic view on Nidersee as soon as you reach the top, where you also can jump into the lake or at least refresh for a bit. Another 10-15 min and you'll reach Leutschachhütte. 

