The Columbia River Exhibition of History, Science and Technology (CREHST) museum's ABC Tours showcase the history of Richland's Alphabet Houses including plans, photographs and project-related Dupus Boomer cartoons. Built as part of World War II's top secret Manhattan Project, the federal government was faced with the immense challenge of creating one of the first master-planned communities in the nation. The houses were assigned a letter designating their architectural design, and employees of Dupont and the Manhattan Engineering District were assigned certain style homes based on their rank and position. During a two-year period, a total of 3,740 new homes were constructed to house the rapidly growing workforce. Group Alphabet House Tours are held at various times throughout the year and generally include an AA-Z house plan book. Advanced arrangements required. For more information contact CREHST Director, Gwen Leth at 509-943-9000 or gwen@crehst.org.