Tourists (some German) swim in Lake Eacham in Northern Queensland, Australia. The kicking splash sound was a boy on a body-board kicking along.
Scientists believe Lake Eacham was formed approximately 12,000 years ago when magma rose to the surface and heated the water table and caused crater-sized explosions. Eventually water filled the craters and the trees grew back, creating the tranquil lake used today by families and tourists for recreation. The lake is fed by underground springs so it retains a constant water level and is unaffected by drought.
Lake Eacham is 60 metres deep, and features a pontoon great for diving into the deep water. A large grassy area is terrific for picnics, sunbathing, or just watching the kids as they play in the shallow water near the edge of the lake.