Next to Gotham City, the most famous fictionopolis in all of comics is Metropolis. No doubt this is due to its most famous adopted sons, men known as Superman, and of course their memorable supporting casts. On Earths One and Two, this is the largest city in America, and located directly opposite Gotham City, both cities dvided by a long bay leading to an ocean. The Atlantic? Perhaps, although this is never definitely verified.
Among the many notable buildings in both world's Metropolis are its tallest skyscraper, known as the Metropolis State Building on Earth-One and the Emperor Building on Earth-Two, as well as the Metropolis Museum of Natural History, Metropolis Planetarium, Metropolitan Museum on each. The major sports stadium within city limits was named Metropolis Stadium on Earth-One and Sportsman's Stadium on Earth-Two. The biggest similarity, and difference, between the two fictional burgs is its predominant newspapers, the Daily Planet and Daily Star, which beat out its rivals in both scoops and award-winning journalists... including two sets of Clark Kents, Lois Lanes, Jimmy Olsens and Perry Whites. In one timeline wherein the Multiverse was transformed into a single positive matter universe with a single Earth residing therein, a duplicate of Earth-Two's Metropolis had (much like Earth-One's Kandor) been created in an adjoining pocket dimension.