Lake Avernus- Aeneas and the Cumaean Sybil Joseph Mallord William Turner (1775-1851)

The picture has something of this: tree, landscape, mountain, people, water, river, rock, seashore, island, wood, hill, scenic, sunset, beach, outdoors, dawn, daylight.
Perhaps it’s a painting of a man standing in front of a body of water with a group of people on either side of him and a mountain range in the background.