Nagas and Garudas - animals with miraculous powers

Nagas are animals with miraculous powers who live in many places: in some realms of the gods or humans, bellow the four continents or in depths of waters (oceans, rivers, lakes, etc) where they have their own paralel reality, invisible to us, with cities, palaces and various manifestations. Sometimes, it seems that the waters are just a portal towards their realms which they can reach through other means