Algar do Carvao With Picturesque Lake At The Bottom Fed By Rainwater In Terceira Island, Portugal

algar do carvao cave lake bottom rainwater terceira island portugal nature azores geology tourist attraction angra do heroismo basaltic porto judeu water picturesque dark geologic lava high angle geological stone volcano terceira island landscape algar carvao volcanic vent inside destination travel europe lava tube environment landmark scenic tourism attraction park light volcanic volcanic cave rock touristic cavern portuguese illuminated natural