IN an epic achievement retracing the steps of his great-grandfather more than 100 years ago, Mark O’Brien arrived in Toowoomba on Saturday after walking almost 1000 kms from Sydney.

The journey took him just three weeks — the equivalent of completing 21 marathons in 21 days.

Inspired by a wheelchair-bound friend, the Armidale investment adviser took on a self-imposed challenge to honour his ancestor and raise research funds for SpinalCure Australia at the same time.

By the time Mr O’Brien and about 100 members of his family celebrated at The Spotted Cow on Saturday night, he had raised $60,000 towards the dream of helping people like his friend James Horsborough walk again.

"My great-grandfather Michael Stephen and his sister Mary arrived in Sydney from Lebanon in 1898 and walked all the way to Toowoomba," Mr O’Brien said.

Coming from a small country, the pair had no idea of how far they would have to travel. They spoke no English and knew nobody.

All they had was a piece of paper with their sponsor’s Ruthven Street address on it. They got to Toowoomba by showing the address to people they met along the way and following their directions.

"I am amazed they did it, and amazed I could do it too," Mr O’Brien said

On Saturday members of the extended O’Brien, Stephen, Betros, Boulous, Abood, Joseph, Lahood and Hanna clan formed a guard of honour for Mr O’Brien at the Toowoomba Railway Station, his ancestor’s point of arrival.