In early 1973 the Marriott Corporation approached the Village stating that they wanted to build an Amusement Park near the interchange of Highway 132 and the Tollway. Many hearings were conducted and then the Village and the Marriott Corporation entered into an Annexation Agreement for Special Use to construct an amusement park. An advisory referendum was held and the people of Gurnee voted overwhelmingly (773 yes vs. 252 no) to approve the construction of the facility. Design The 300-acre theme park was designed for Marriott Corporation by the world famous motion picture set designer and architect, Randall Duell, of Santa Monica, California. His creativity contributed to the detail that went into the crafted designs and original architecture of the Park. The planning process began in early 1972 with the Park eventually opening in 1976.

After extensive demographic studies, Economic Research Associates chose Gurnee, Illinois, as an ideal location for a theme park that could accommodate over two million guests annually. Economic Research Associates is the same firm that determined the impact and long-term feasibility studies for Walt Disney World in Orlando, Florida, and many other major U.S. theme parks. Over 700 construction workers and crafts people assembled during 24 months of construction to create Great America and its more than 100 buildings and attractions. Exactly 715 days after the ground breaking ceremonies on June 14, 1974, then named Marriott's Great America held its Grand Opening on May 29, 1976. Marriott Corporation opened an identical sister park in Santa Clara, CA in April 1976.