The "Reserva Natural das Dunas de São Jacinto" is a national park (an area reserved for the protection of natural habitat of plants and species) and is located at the tip of the stretch of land that goes form Ovar to S.Jacinto.
To the west you have the Atlantic Ocean and on the east side the "Ria de Aveiro" estuary. This is a 700 acre protected area, created in 1979 and integrated in a larger area for teh Special Protection of the Ria de Aveiro. Inside the reserve area the National Scouts have a training center.
See the web page of Turismo do Centro
Reserva S Jacinto