Here we are now in the Dome Hall: immediately drawing our attention is a circular stalagmite with smooth walls which, joined to the ceiling, truly resembles the shape of a dome. After the holy water font and the organ, the Cave continues to spark our imagination, almost as if to reaffirm the sacredness of this place.
But to move from the sacred to the profane, all we need to do is look up: hanging from the ceiling, just to the right of the dome, we can spot a very unusual stalactite which, besides being hollow inside, appears to curl around itself. This is the Tobacco Leaf. Who knows whether the English captain William Henry Smyth — geographer and cartographer who visited the Cave in the early nineteenth century and drew one of its maps — noticed the resemblance as well. For a time, this hall even bore his name. Today, however, his name still lives on in Mare Smythii, which is not underground, nor even on Earth, but near the equator of the Moon. Surely that will suffice for him.
Turning our gaze to the right, near a small staircase, we find the entrance to the Cave’s speleological route, closed to the public for safety reasons. The internal extension of Neptune’s Cave, including all its branches, stretches for about three kilometres: a dense and complex underground network made up of galleries and tunnels arranged on overlapping levels — a magical world filled with wonders, deep lakes, and incredibly thin limestone filaments. Even today, speleologists continue to explore this marvel with courage and skill, though unfortunately — or perhaps fortunately — it remains inaccessible to ordinary visitors. All that remains is to admire the photographs or, for the more romantic souls, to rely on their imagination.