The city's great strength is its architecture. Walk Elmwood Avenue and Delaware Avenue for the turn-of-the-century mansions, tour Frank Lloyd Wright's Darwin Martin House complex on Jewett Parkway, and look up at Louis Sullivan's Guaranty Building downtown — one of the earliest steel-frame skyscrapers. The Albright-Knox / Buffalo AKG on Elmwood is the one essential museum. Canalside on the waterfront has been rebuilt into the city's best public space. And Niagara Falls is half an hour away.