Belvederes are structures, usually of stone or wood, that offer a scenic view of the surrounding environment. Antonyms for this word would be structures that do not provide such a breathtaking view, such as dark tunnels, underground caves or enclosed buildings without windows. Other antonyms could be wastelands or barren plains, where there is nothing noteworthy to look at, or areas obscured by thick fog or dense forest canopies, which do not allow for clear views of the surroundings. Basically, any structure or environment that does not offer a panoramic or awe-inspiring view of the surroundings can be seen as an antonym of a belvedere.