The Tri Hub went up in a matter of hours yesterday afternoon as athletes ranging in age between 10 and 18 trekked into the nearby Union Boat Club to register.
Many also took the time to stretch the muscles after their journey to the River City with training runs, cycles and even swims ahead of the 5pm official opening by Whanganui iwi performing a powhiri.
The events, starting at 8am today, include the individual triathlon, the team triathlon, the aquathlon duathlon and the team tag triathlon that replaces the open swim from previous championships.
Road closures began yesterday with a section of Somme Pde set aside as the transition area.
During the closures directional signs will be in place to show motorists alternative routes.
The road closures are:
* Taupo Quay between Bates St and Market St: today 5pm-8pm; and tomorrow 5pm-8pm.
* Taupo Quay between Drews Ave and Bates St: Today 7.30am-5pm; tomorrow 7.30am-5pm.
* Somme Pde between Bates St and Glasgow St: Today 7.30am-5pm.
* Somme Pde between Bates St and Dublin St: tomorrow 7.30am-5pm.
* Dublin St Bridge: Today 7.30am-5pm.