Maitencillo has several beaches in town or more options to the north.  Within 10 minutes, you can visit the beaches of Cachagua and 15 minutes, you can enjoy Zapallar.  The coastline in this part of Chile is amazing and worth exploring.  The Pacific Ocean with its Antartic current can be a little cold but refreshing in the summer.  Maitencillo has several local bars and restaurants with great food and atmosphere.  Be sure and go to the Canasta Bar on Avenida del Mar!