dark and rough texture with moss wall in tunnel opening to the outside light in algar do carvão, terceira - azores portugal

active algar angra attraction azores açores basaltic carvao cave cavern caves coal damp dark destination entering environment europe famous fern foliage fresh geologic geological geology green heroismo illuminated inside island judeu landmark landscape lava leaves light monument moss natural now opening outdoor outside park pattern plant porto portugal portuguese rock rough scenic spot stone terceira texture textured tourist touristic travel tube tunnel underground vegetation volcanic volcano wall wallpaper was where