About 50,000 have taken part in a union protest against austerity cuts and NHS changes during the Conservative Party conference in Manchester.
The march, which set off from Liverpool Road at 12:15 BST, passed through the city centre and ended with speeches in Whitworth Park.
Greater Manchester Police described it as one of the largest protests they had ever policed.
The 2013 Conservative Party Conference started earlier at Manchester Central.
Frances O’Grady, TUC general secretary, said: “Austerity is having a devastating effect on our communities and services, with 21,000 NHS jobs lost over the last three months alone.
“The NHS is one of Britain’s finest achievements and we will not allow ministers to destroy, through cuts and privatisation, what has taken generations to build.”
Andy Burnham, Labour’s shadow health secretary, said: “David Cameron needs to be forcefully reminded that he has never been given the public’s permission to put the NHS up for sale.
“These figures reveal the frightening scale and pace of NHS privatisation since Cameron’s Health Act came in.”
Children’s charity worker Jo McSwaine, 22, from Manchester, said: “I don’t believe in cutting public services, that’s the biggest thing. We have to look after everyone, not just the rich”.
Her mother Judith McSwaine, 61, who travelled from Newcastle to attend, described the turnout as “absolutely fabulous.”
Catharyn Lawrence, a Unison regional organiser from Wakefield, said: “This will show we are a collective force. It is great people are standing together.”
Protesters dressed as zombie doctors and nurses perform a dance routine to Michael Jackson’s Thriller
A Department of Health spokeswoman said there was “absolutely no government policy to privatise NHS services”.
She said: “The NHS will stay free for everyone, but it’s right that patients should get the best service – regardless of who provides it.
“Charities, social enterprises and independent providers play an important part in providing NHS care – and have done for many years – helping give patients more choice of where and how they are treated.”
Greater Manchester Police said only two arrests were made.