The Penistone man died at the age of 31 after injuries following a victory in a 10-round light heavyweight contest against Dec Spelman.
Friends and admirers connected to the Hillsborough-based Sheffield Boxing Centre assembled on Sunday morning to walk the three miles around the Damflask Reservoir in Loxley Valley.
SBC owner Glyn Rhodes said the walkers had wanted to honour the memory of Westgarth, who was a Northumberland born hotel chef.
"People have come out to celebrate his life” said the trainer.
"The reason we walked around Damflask was that this is where Scott and all the lads always used to meet up and run round on a Saturday morning - so what better place to do it than the place that Scott used to actually do his road work.
"I am more than impressed by the turnout, it is unbelievable."
Rhodes said moving on from the tragedy has been difficult.
"We are still waiting on the inquest.
"I was told the coroner's report would be in February but that is not looking likely now.
Rhodes said you could tell what a popular man Westgarth was, by the size of Sunday's turnout.
Westgarth's opponent has tweeted his own tribute.
"A year to the date. A great man lost his life whilst doing what he loved! It was an honour to share a ring with you. Thinking about the Westgarth family as always."
Promoter Carl Greaves added: "1 year ago we lost a gentleman and a real fighting man in tragic circumstances a night I will never forget. My thoughts are with @dec_spelman who's keeps fighting on in memory of Scott."