Exploring Douro River by boat, Mosteiro da Serra do Pilar over the mountainous area

exploring douro river boat trip mountains mosteiro da serra do pilar porto portugal rabelo navigating scenic beauty river cruise discovering panoramic views historical site spectacular landscapes santa marinha cultural heritage waterway journey mountainous terrain portos landmarks relaxing voyage vila nova de gaia natural beauty tranquil setting water adventure mannerist monastery memorable excursion iconic attraction douro river discovery visual delight nature and history waterborne travel mountain backdrop sightseeing scenic escape cultural treasure waterway perspective portos waterfront outdoor adventure historical architecture waterway tour scenic tour natures embrace portos appeal breathtaking landscapes picturesque journey porto exploration river and mountains harmony world heritage by unesco