Rome is surrounded by beautiful volcanic lakes. Vico, Bolsena, Albano can all be easily reached from Rome and offer not only scenic views but also little beaches and clean waters to dive in or row, since engine-driven boats are forbidden. But there are many other smaller lakes near Rome.
Besides having a swim, you can also trek or ski in the mountains. Campo Felice is our favorite destination to spend a great winter day on your snowboard or skis. But other places such as Campo Livata or Terminillo will also make you want to get on the snow!