1919 Race, it seems there wasn't a fixed route except for the departure point, arrival at Darwin and reporting points at Alexandria and Singapore?
In early 1919, the Commonwealth Government of Australia offered a prize of ŁA10,000 for the first flight from Great Britain to Australia, under specific conditions. In May 1919, Billy Hughes, Prime Minister of Australia, and Senator George Pearce, Minister for Defence (Australia), in consultation with the Royal Aero Club, stated that valid aircrews must all be Australian nationals, the aircraft must have been constructed in the British Empire, and the journey must be completed within 720 consecutive hours (30 days) and be completed before midnight on 31 December 1920. The departure point must be either Hounslow Heath Aerodrome (for landplanes) or RNAS Calshot (for seaplanes and flying boats), with reporting points at Alexandria and Singapore, and final destination in the region of Darwin. Each flight was to take place under the competition rules of the Royal Aero Club, that would supervise the start, and control the competition generally.
The 1969 England-Australia Commemorative Air Race started 18 Dec 1969 and finished 4 Jan 1970, was won by W. J. Bright and F. L. Buxton in a BN Islander G-AXUD.
http://www.pprune.org/aviation-histo...-air-race.html