panoramic view of the famous neptune's grotto in sardinia, italy, during a scheduled visit with tourists touring the cave

cave grotto column stalactite neptune alghero sightseeing visiting sardinia nature cavern touristic panoramic visit touristy tourist travel geology italy nettuno stalagmite holiday attraction grotte outdoor underground sardegna inside sassari landmark italian illuminated grotta 039 geologic exploration discovery destination famous place exploring stalactites tourists tour adventure tourism island popular lighting unesco view 39aph39 scheduled touring sites