You should have a good level of fitness.
Take your pick - walk to Ben Lomond Saddle (3-4 hours return) or to Ben Lomond Summit (6-8 hours return).
Ben Lomond track is a challenging track with a 1438m elevation gain of the walk. For the first segment, the track begins at the Douglas fir stands via the Skyline Access Road and takes you through the alpine tussocks and shrubs.
Experience magnificent lake and mountain views as you climb up the saddle. The track gets more challenging from here and the walk requires an advanced level of fitness as the last push towards the top of Ben Lomond is very steep as it approaches the summit at 1748m. At the top, you'll be rewarded with exceptional views and on clear days, you can spot Mount Earnslaw/Pikirakatahi and Aspiring/Tititea.