The Koutavos Lagoon is an excellent nature reserve for wildlife, including the Caretta Caretta turtle and other birdlife. It is located near the head of Argostoli Bay. The town's greatest park is a shady forest of eucalyptus and pine trees that may be reached by walking or cycling along the wide trail that round the lagoon from the harbour front. Until the Drepano Bridge was built in 1813 to ease access to Argostoli from the settlements across the bay, the lagoon was an almost impassable bog filled with mosquitoes and malaria. A small islet in the lagoon's center is off-limits to visitors because it serves as a nesting and feeding area for waterfowl. The Koutavos Lagoon is located near the mouth of the Argostoli Bay.