Dozens of candidates will battle it out on Thursday to try and become the elected mayor of one of eight mainly urban areas across England with the promise of significant decision-making powers attracting a number of prominent people to each contest.
Six new super-regions will see mayoral elections for the first time: West Midlands, Greater Manchester, Liverpool City Region, Cambridgeshire & Peterborough, Tees Valley and West of England.
Meanwhile, mayors in Doncaster and North Tyneside are due to seek re-election.
The roll out of so-called "metro mayors" across England is part of the Government's wider plan to devolve greater powers to the regions.
Under the proposals the Government will agree to hand over more powers on things like transport, housing and jobs - but only if local authorities agree to the introduction of an elected mayor.
Here are the frontrunners.
Andy Street, Conservative
Mr Street is the Conservative's great hope in the forthcoming mayoral elections having quit his role as the boss of high street giant John Lewis to run for mayor.
He has pledged to use the business skills he has learnt at the retailer to help drive investment and create jobs in the region.
He also wants Birmingham to host the 2026 Commonwealth Games.
The former managing director of Britain’s best-loved retailer is the Tory's most high-profile candidate and he has repeatedly received the very public backing of the party's leadership with Theresa May telling the Conservative Party Conference in October 2016: "A success in business running John Lewis. An action man in Birmingham, playing his part in transforming this city. A man to get things done, the future Mayor of the West Midlands - Andy Street."
Mr Street has traded in his £800,000 a year salary to run for mayor and if he is victorious in May his salary will be worth some £700,000 less.
Mr Street said that while he loved his job at John Lewis he "just couldn’t let the moment pass" to try and be the first elected mayor of West Midlands.
Mr Street read politics, philosophy and economics at Oxford and became president of the University Conservative Association.
He originally wanted to be a social worker.
Mr Street is not married.
Other notable candidates: Labour MEP and former Birmingham Erdington MP Sion Simons.
Total candidates: Six.
The candidates: Andy Street (C), Sion Simon (Lab), Beverley Nielsen (LD), James Burn (Green), Pete Durnell (UKIP), Graham Stevenson (Comm).
Andy Burnham, Labour
Mr Burnham has been on the frontline of British politics for a decade having been first elected as the MP for Leigh back in 2001.
He rose through the ranks under the Labour governments of Tony Blair and Gordon Brown, first becoming chief secretary to the treasury, then culture secretary and finally health secretary.
He then became a prominent member of the Labour shadow cabinet after the party lost power in 2010, serving as shadow health secretary and shadow education secretary.
Mr Burnham attempted to become Labour leader in 2015 after the resignation of Ed Miliband following the party's defeat at the general election.
Despite entering the race as the favourite he ultimately lost out to Jeremy Corbyn, coming in a distant second place.
Mr Burnham served in Mr Corbyn's shadow cabinet but resigned from his role as shadow home secretary in October 2016 in order to focus on his mayoral bid.
He has committed to quitting as an MP if he is elected mayor which will trigger a by-election in his Leigh constituency.
Mr Burnham has also been a vocal supporter of the families of the victims of the Hillsborough disaster, fighting to secure justice for those affected.
He is married with three children and is a lifelong fan of Everton FC.
Other notable candidates: Trafford Council leader Sean Anstee for the Conservatives, and Trafford councillor Jane Brophy for the Lib Dems.
Total candidates: eight
The candidates: Sean Anstee (C), Andy Burnham (Lab), Jane Brophy (LD), Will Patterson (Green), Shneur Odze (UKIP), Stephen Morris (Eng Dem), Marcus Farmer (Ind), Mohammad Aslam (Ind).
Liverpool City Region
Steve Rotheram, Labour
A close ally of Labour leader Jeremy Corbyn, Mr Rotheram is currently the Labour MP for Liverpool Walton.
He was first elected to Parliament in 2010 and was re-elected in 2015 but he will quit the Commons and trigger a by-election if he becomes mayor - something which is extremely likely given the area’s historic support for Labour.
Mr Rotheram is one of eight children and left school at 16 to work as a bricklayer, travelling to the Falkland Islands to help rebuilding efforts following the conflict between the UK and Argentina.
He won the Labour nomination for mayor by defeating the current elected mayor Joe Anderson and Labour MP Luciana Berger.
Total candidates: Eight.
The candidates: Tony Caldeira (C), Steve Rotheram (Lab), Carl Cashman (LD), Tom Crone (Green), Paula Walters (UKIP), Paul Breen (Jury), Roger Bannister (TUSC), Tabitha Morton (Women).
Cambridgeshire & Peterborough
Notable candidates: East Cambridgeshire District Council leader and Cambridgeshire county councillor James Palmer is running for the Conservatives, Cambridge city councillor Kevin Price for Labour, Cambridge city councillor Rod Cantrill for the Liberal Democrats, and Cambridgeshire county councillor Paul Bullen for Ukip.
Total candidates: Seven
The candidates: James Palmer (C), Kevin Price (Lab), Rod Cantrill (LD), Julie Howell (Green), Paul Bullen (UKIP), Stephen Goldspink (Eng Dem), Peter Dawe (Ind).
West of England
Notable candidates: Former Bristol West MP Stephen Williams for the Lib Dems, South Gloucestershire councillor Tim Bowles for the Conservatives, NHS manager Lesley Mansell for Labour, and local businessman John Savage, standing as an independent.
Total candidates: Six
The candidates: Tim Bowles (C), Lesley Mansell (Lab), Stephen Williams (LD), Darren Hall (Green), Aaron Foot (UKIP), John Savage (Ind).
Notable candidates: Redcar & Cleveland Council leader Sue Jeffrey for Labour
Total candidates: Four
The candidates: Ben Houchen (C), Sue Jeffrey (Lab), Chris Foote Wood (LD), John Tennant (UKIP).
Total candidates: Six
The candidates: George Jabbour (C), Ros Jones (Lab), Brian Whitmore (UKIP), Eddie Todd (ND), Steve Williams (TUSC), Chris Whitwood (Yorkshire).
Total candidates: Four
The candidates: Stewart Hay (C), Norma Redfearn (Lab), John Appleby (LD), Stuart Houghton (UKIP).
The polls on May 4 coincide with county council elections in England, elections for all councils in Scotland and Wales, and a Commons by-election at Manchester Gorton following the death of veteran Labour MP Sir Gerald Kaufman.