Hercules and the Lernaean Hydra Gustave Moreau (1826-1898)

The picture has something of this: cave, water, rock, stalactite, subway system, limestone, people, river, landscape, light, grotto, exploration, geology, nature, tree, stone.
Perhaps it’s a painting of a man and a woman in a cave next to a body of water with a bird perched on top of the man’s head.