Dive into a world of crystal waters, where you can see the marine life in their untouched and protected habitat, the Arrábida National Reserve Park.Head to the Arrábida National Reserve on this half-day tour from Lisbon. Snorkel in the crystal-clear waters of the Atlantic Ocean and discover the abundant marine life of the area. Take a sightseeing trek through the Arrábida Mountains where you can admire the views of the beautiful coastline below and soak up the sun.