Lake Stymphalos (Stymphalia), hidden away in a dream-like setting between Arcadia and the Argolid, is a vast, marshy, expanse bristling with reeds. Designated a Natura 2000 site, it provides refuge to myriad birds, fish and tiny green frogs that leap as soon as you approach the shore. On the west shore, there is an elegant contemporary building that houses a museum dedicated to this wetland.