From the Back of the Box:
Add a new dimension to your role-playing or miniatures gaming--the third dimension! This box contains 30 sheets of colorful fold-up buildings. Assembly is simple because all the pieces are die-cut and pre-scored; all you need is glue. Also included are three full-color, two-sided mapsheets showing street layouts, plus a 16-page booklet describing how to assemble the buildings and how to modify and reassemble them in new and unusual ways.
The pieces in this box are drawn from previous TSR publications, including Castles, Falconmaster, Flames of the Falcon, and the original Cities of Mystery set.