Even on a tight schedule, Lake Vouliagmeni earns the hours.
Allow 2–4 hours.
Swimming in the mineral-rich, 22–29°C lake under sheer rock walls is a genuinely unusual, restorative experience — and the little fish nibbling your feet are a free pedicure. The catch: it's a managed pay-entry facility (~€12+) with sunbeds, it gets busy in summer, and it's well out of the centre on the southern coast.