Racing identities, politicians, battlers and punters have filled Sydney's St Mary's Cathedral to farewell Bart Cummings, the man known to all as the Cups King.

Cummings' large family led mourners at the state funeral, but behind them was a congregation that exemplified the people the trainer had touched during his 87 years.

NSW Premier Mike Baird and his wife Kerryn, state Labor leader Luke Foley, federal Health Minister Sussan Ley and Governor-General Sir Peter Cosgrove were present, as was leading trainer Gai Waterhouse, many of the country's current and former top jockeys.

Archbishop of Sydney, Anthony Fisher, said Cummings was revered by Australians of all sorts.

"From the cabbies who drove him to Randwick and Flemington to leaders of government and industry, even the Queen," he said.

The priest who gave the homily, Father Adrian Meaney, said Cummings had passed away peacefully on Sunday, August 30, at his home beside the Nepean River in Sydney's northwest.

"Bart finished his race of a lifetime," Fr Meaney said.

"He had run his race with great courage." Cummings' wife of 61 years, Valmae, sat at the front of the cathedral.

She had celebrated her 61st anniversary with Bart the Friday before he died.

Beside Cummings' coffin were placed the 1996 Melbourne Cup won by Saintly and a statue of the Virgin Mary - symbols of the two religions in the devoted Catholic's life.

As the crowd left after the service the bells of the cathedral tolled 87 times, one for each year of Cummings' life.

Princes Farm was everything the legendary trainer of 12 Melbourne Cup winners had wanted in life and it's right that he died there a week ago, son Anthony Cummings has told mourners at his father's state funeral in Sydney.

"(It was) a touch of Ireland, a touch of New Zealand, a lot of Bart," Mr Cummings told the large congregation who gathered at St Mary's Cathedral.

"He and mum lived there over the last few years and mum supported him as she had done all of her life - 61 years, a couple of days before he passed."

Mr Cummings fought his tears as he spoke of his father's common touch in the sport of kings.

"He treated all equally and gave them time. In the end, dad was more than a horseman - (he was) an icon, a legend, all of that, built from flames and hardship to go with success. Bob Hawke described him as a great and good Australian."

And that was enough, Mr Cummings said.

He spoke too of the awe he felt for his father as people sought out his advice.

"(They) didn't always get - didn't like - what they were told, but what they got was what they asked for: his view, unequivocal, unabashed, uncensored."

He told mourners his father had his share of ups and downs throughout a career spanning more than 60 years, not the least of which being the health problems that plagued him in the final year of his life.

"... but as we'd seen all the way through, there hadn't been a bridle made to hold him back," he said.

Sydney Archbishop Anthony Fisher said Cummings never lost his down-to-earth style despite his incredible career.

"He was revered by Australians of every sort, from the cabbies who took him to Flemington and Randwick, to leaders of government and industry who liked to be seen with him," told mourners.

"Even, I'm told, that great connoisseur of horse flesh, Her Majesty the Queen."