This is the Stevens International 950+ piece Chicago 4D Cityscape Timeline Puzzle. 4D Cityscape puzzles recreate world famous City skylines, but not only in three dimensions (using scale-model buildings). 4D Cityscape puzzles also feature the axis of fourth dimension time, spanning over 100 years of architectural history. The puzzle includes many detailed plastic replicas that depict the city as it appeared as far back as 1800 through to the present and future. Each puzzle includes famous monuments, buildings, skyscrapers, bridges, and more allowing you to build the city from the era that you choose! The streets glow in the dark, emphasizing the city’s glow. The included Time Poster provides you with a detailed history of the city, while the online educational feature gives you access to more than 2000 facts.