Lake Burley Griffin in Canberra was completed in 1964.
Construction began in earnest in 1960, after decades of delay following Walter Burley Griffin’s original plan for Canberra. The Scrivener Dam was locked on 20 September 1963, beginning the lake’s filling, but a prolonged drought slowed the process. The water finally reached its planned level on 29 April 1964.
The lake’s completion is generally associated with its formal inauguration on 17 October 1964, when Prime Minister Sir Robert Menzies commemorated the filling and completion of the project’s first stage. This explains why 1964, rather than 1963, is the standard answer. The earlier date marks the dam’s closure, while the later date marks the finished lake and its public opening.
The lake was named for Griffin, the American architect whose winning Canberra design placed a large ornamental waterway at the city’s centre.