Isla Victoria is a small island located in Nahuel Huapi lake, which is part of the park by the same name. The lake is one of the main defining features of this part of Patagonia, with the city of Bariloche on the south shore, and smaller town of Villa La Angostura on the north side.
Victoria Island is located in the middle of the northernmost branch of the lake and is accessed from Puerto Pañuelo, a 30-minute drive from Bariloche. There are a couple of sailings daily, some of which continue to Parque Nacional Los Arrayanes, specificially, to the Quetrihué peninsula, which is home to the rare protected arrayán (Chilean myrtle) forest, with slender, cinnamon-barked trees which grow in a dense grove, and some examples of which are up to 650 years old.
Isla Victoria has varied foliage, including the arctic beech, and some easy hiking trails, and if you spend time wandering, you can find some solitary beaches on which to sit and contemplate the lake, or take a chillly dip. Many visitors do this trip as a half-day tour, though you could spend longer on the island. The weather can be cool, especially if you opt to sit outside on the boat, so plan accordingly.
There are a couple of trips daily, in the morning and early afternoon, and you can choose between taking your own transportation to Puerto Pañuelo, or taking a complete tour. If you go on your own, you can just go back and forth to Isla Victoria, but the tours generally go to Parque Nacional Los Arrayanes, which is a good way to see both places by boat, particularly if you are short of time.