This 4D Cityscape puzzle collection allows you to build history over the "4th Dimension of Time." This 950+ piece puzzle puts together the history of the USA with 3D replicas of monuments, buildings and geographic features. Starting with the first jigsaw layer, the puzzle showcases the evolution of the country based on the territorial expansion from the year 1783 through the 1900s. The second jigsaw layer assembles a modern map, featuring the formation of each of the 50 states in a time sequence based on the dates of established statehood. The third jigsaw layer places 93 of the most famous US monuments and buildings on the map in the order in which they were constructed. 950+ puzzle pieces, 93 3D monuments. Includes a "4D Time Poster," which notes famous constructions by date. Fully assembled: 24" length x 16" width x 2" depth. Ages 8+.