| Date | Event |
| 1924 | Thomas Armstrong donates platform mound and approximately five acres of surrounding area to the City of Phoenix. |
| 1924 | Omar Turney, City of Phoenix Engineer, convinces city to purchase the Park of Four Waters, approximately 10 acres, south of the platform mound. |
| 1929 | Odd S. Halseth becomes first City of Phoenix Archaeologist and director of Pueblo Grande Museum. |
| 1933-1934 | First Museum building constructed of adobe west of platform mound. |
| 1936 | Approximately three acres of land west of platform mound purchased. |
| 1951 | Approximately 11 acres of land north of platform mound purchased from Tovrea Stockyards. |
| 1960 | Donald Hiser becomes City of Phoenix Archaeologist and director of Pueblo Grande Museum. |
| 1963 | Park of Four Waters becomes a National Historic Landmark. |
| 1964 | The platform mound and surrounding area becomes a National Historic Landmark. |
| 1968-1986 | Approximately 72 additional acres of land purchased, bringing total acreage of Pueblo Grande Museum and Cultural Park to 102.27 acres. |
| 1974 | New Museum building constructed, replacing old adobe one. |
| 1974 | Pueblo Grande becomes a single National Historic Landmark. |
| 1977 | Pueblo Grande Museum Auxiliary founded. |
| 1977 | Pueblo Grande Museum holds its first Indian Market. |
| 1984 | David E. Doyel becomes City of Phoenix Archaeologist and director of Pueblo Grande Museum. |
| 1988-1990 | National Park Service evaluates eroded condition of Pueblo Grande ruins and conducts stabilization of the platform mound and ballcourt. |
| 1989 | Pueblo Grande Museum Archival Project begun. |
| 1990 | Roger W. Lidman becomes director of Pueblo Grande Museum and Todd W. Bostwick becomes City of Phoenix Archaeologist. |
| 1995 | Two additional buildings added to Museum complex, permanent collections storage and a community room, doubling the size of the Museum's facilities. |
