frio river at caño negro wildlife refuge, costa rica

river frio caaplusmn onegro wildlife refuge costarica nature travel tourism waterway ecosystem biodiversity conservation centralamerica flora fauna landscape scenic wetlands sanctuary adventure explore ecotourism greentravel sustainable rainforest jungle cloudy tranquil remote natural reserve tropical exotic destination hiking trekking outdoors environment pristine unspoiled serene getaway holiday vacation sightseeing untouched authentic purity heritage