This lake is not as popular as Lake Rotoiti, but just as beautiful. You can do some walking here to, ranging from 20 minutes to 2 hours. Just walk fast, because there are a lot of sandflies around there!
You can do a lot of walks from here, most are starting at Kerr Bay. The walks range from 15 minutes to 6 hours. When we were there the forest was all blackened so our 1.5 hour walk wasn't very beautiful, but that was just a temporary problem hopefully.
Mount Angelus (2075m) is part of the Nelson Lakes National Park, and sits between Lakes Rotoiti and Rotoroa. which, funnily enough, is close by Nelson, but even closer to the little holiday resort of St Arnaud, at the north end of Lake Rotoiti.
The most spectacular hiking access is along the Robert Ridge - a consistently high, sometimes narrow and usually beautiful route. There are great views into the basins above the Travers Valley and alpine herbfields for budding botanists.
The high altitude along the plateau there (up to 1600 metres) means that this area is subject to bad weather (including snow) at any time of the year. The steep slopes to either side are prone to avalanches in winter. This is a popular area even in winter with ski-tourers on the ridge and frozen lake and climbers tackling snow and ice on Mt. Angelus.