Ashburton College year 13 pupils Matt Jopson, Ben Connor and Joe Langley are biking 500km, from Ashburton to Invercargill, to raise funds and awareness of prostate cancer.
The trio said they decided to raise awareness of the disease as they were "all guys" and thought it was a worthwhile cause.
The young men left Balclutha yesterday afternoon for Gore, and plan to leave Gore this morning for the final leg of their journey - the 65km ride to Invercargill.
The trio have been accompanied throughout the journey by fellow pupils Andrew Robertson (18) and James Smith (18) in two support vehicles.
The group left Ashburton on Tuesday, and are due to arrive at the finish line in Invercargill today.
Matt said the group had been overwhelmed by the support from the public.
"We've had really good support - lunches, food donations, and good [monetary] donations."
About $3000 had been raised by the trio so far, and they hoped to meet their $5000 target.
All agreed the Kilmog hill near Dunedin had been the most difficult part of their ride.
"It was just so steep - it was demoralising," Ben said.
The group will be met by Invercargill Mayor Tim Shadbolt and a member of the Prostate Cancer Society when they arrive in the city today.
Their fundraising page is: http://www.everydayhero.co.nz/raging-bulls
