The city-wide benefits of hosting the David Jones Suzuki New Zealand Schools Triathlon Championships was touted at the event's launch on Wednesday night.
Whanganui Mayor Annette Main said the city had a proven record of hosting such events, and sporting events in particular were something the city had an opportunity to keep attracting.
About 600 athletes along with their supporters are expected in town for the March 30-31 event.
"The other thing I like about this event is it is going to be in the central city, so we've got a much better chance of that economic benefit being spread throughout," she said at the launch.
Event manager Rachel O'Connor said a tri-hub area in the central city would bring "significant economic benefits", while Sport Whanganui chief executive Danny Jonas said it would be a "truly Whanganui event".
"It's right on our back doorstep, so let's flood the entries," he said.
Tri NZ technical and events adviser Shanelle Barrett was in town for the launch and said several Olympic athletes had started at the Schools event.