From Qantas:
To celebrate our 100th year, we’re offering 100 airfares each day for $100^ each way when purchased as a round trip.
We’re taking off into our 100th year and, as the world’s oldest continuously operating airline, we’d like to thank you with a once in a century sale.
Over the next four days, we’ll be releasing 100 airfares each day to Australia for $100 each way when purchased as a round trip for selected city pairs and travel dates. Fares will be released at approximately 2pm PST/5pm EST each day from Monday, 18 November to Thursday, 21 November 2019 until sold out.
