The Secret Lagoon, also known as Gamla Laugin, is one of Iceland's oldest natural swimming pools located near Flúðir. Built in 1891, this unique spot is fed by geothermal hot springs like Vaðmálahver and Litli Geysir, providing warm, sulfur-rich water at a constant temperature of 38-40 degrees Celsius year-round. With a rich history dating back to the early 20th century, the Secret Lagoon offers a relaxing and authentic Icelandic experience for visitors of all ages. Don't miss out on this gem for a soothing soak in nature's own hot tub!