For more than 20 years, National Rock and Sculpture has been using concrete to build scenery for almost any setting. Its creations include rockscapes, castles, lighthouses, large animals, fairy-tale creatures, and cartoon characters. Examples of the firm's work can be seen at Glendale Adventure Mini Golf, Glendale Heights, Ill. National Rock was responsible for building the course's main attraction - a 23-foot-tall concrete castle - and several concrete rockscapes. Construction of the 18-hole course, from site excavation to final landscaping, ran from January through early May 1992. National Rock completed the concrete structures in about 3 weeks.