More than 30 jet boat teams from around the world will descend on Glendhu Bay tomorrow (Tuesday October 17) to compete in four legs of the NZ UIM World Jet Boat Marathon on the Matukituki River.

The Matukituki stop is one of seven days of racing across the South Island which started yesterday (October 15).

River Racing NZ said it was thrilled to see racing get underway, marking seven years since the world event last came to New Zealand.

Racing is expected to be spectacular as boats reach speeds up to 230 kilometres per hour, with some boats powered by jet turbines.

Boats can reach speeds of up to 230kph.

The first of the four legs begins at 9am tomorrow morning at Glendhu Bay when competitors will depart at one-minute intervals racing 45 kilometres upstream to Beech Forest.

Boats then depart Beech Forest at 11am racing 40 kilometres downstream to West Wānaka with a return leg at 1.30pm.

For the final leg the boats race back to West Wānaka from Beech Forest at 3pm.

As well as racing on the Matukituki River, competitors will also line up on the Kawarau River, Dart River, Waitaki River, Rakaia River, Waiau River, and Waimakariri River. See the full programme here.

PHOTOS: River Racing NZ